Sunday, November 27, 2022

How to Stop the Ukraine War

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This was also submitted as a potential article to the Waco “Trib” 11-24-2022,  and sent 11-28-2022 as a letter to the President of the United States.

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This article was used as a board of contributors item in the Waco "Trib" Sunday 12-4-2022.

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Whatever that was,  that fell in Poland and killed 2 civilians,  it came closer to starting direct war between Russia and NATO,  than anyone wants to admit in public.  There is some reason to believe the story that this was a Russian-made air defense missile fired by Ukraine that went astray,  and there is also some reason not to believe it.  Either way,  something like this is liable to start the war with NATO that goes out of control,  leading to nuclear war. 


I think pressuring Ukraine to negotiate with a Russia still occupying and destroying Ukraine,  is misguided at best,  and probably morally wrong!  Russia rarely negotiated in good faith as the Soviet Union,  and it is still behaving that same way under Putin today.  Nothing Putin (or any of his minions) says can be trusted,  that much we know for sure,  given the last 8 years' history regarding Ukraine.  But we do know they understand and fear the risks of war with NATO.  There’s a 7-decade history for that.

I would therefore recommend that we leverage those fears with a 3-fold ultimatum from NATO to Putin: 

(1) If a Russian-made weapons falls in a NATO country again,  regardless of whoever fired it,  then NATO is at war with you.  Such is a presumptive attack,  and response is thus an Article 5 thing.

(2) If any weapons hit that nuclear power plant in Ukraine,  regardless of who fired them,  then NATO is at war with you.  Radioactive fallout hitting NATO countries is also a presumptive attack,  and thus an Article 5 thing.

(3) If you continue (past a stated short-term date) committing war crimes in Ukraine by targeting civilians and civilian infrastructure,  deliberately or not,  then NATO is at war with you. 

Then move very large armies into place,  on NATO’s side of all the relevant borders,  to enforce it.  The notion is “Putin,  stop the war,  or be destroyed”.  It’s that ugly and risky,  and also that simple. 

I see no other way to stop this,  and stop it we must.  Putin’s war damages us all economically and politically,  and it is utterly catastrophic for Ukraine,  besides threatening nuclear destruction for us all. 

Do that ultimatum,  and I think you will see Putin stand down and withdraw from Ukraine,  rather than risk his personal destruction in a war that he knows he cannot win (nobody wins a nuclear war).  Withdrawal is then his only path to staying in power in Russia.  

Although,  his own people might then have something to say about that,  and good riddance,  too!  A Russia without Putin could be a good friend.

Otherwise,  Putin will continue destroying Ukraine and its people as if they were vermin,  his revenge for their leaving Russia after the fall of the Soviet Union.  That ugly description of deliberate genocide is precisely the real pattern of his Ukraine war so far!  Most of our diplomats and politicians won’t tell you that ugly little truth,  but I just did!  I’m old enough to recognize it when I see it.

And the longer this evil goes on,  the more likely this war will get out of control,  as Putin gets ever more desperate to avoid the humiliating defeats he has been suffering on the Ukrainian battlefield.  The more desperate he gets,  the more likely he will use tactical nuclear weapons against Ukrainian cities.

He will use them for his personal revenge,  they cannot conquer what his armies failed to conquer.  And yet we all know that event could well start the “big one”. 

Time is not on our side. 

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Update 12-8-2022:  Recent news reports indicate that Ukraine has found a way to strike military targets and support infrastructure hundreds of miles inside Russia.  They found a way to do this despite the fact that the US and NATO have not supplied strike weapons of sufficient range for that purpose.  Ukraine has been the west's proxy opposing Putin,  and deserves better:  it is past time to supply the strike weapons to bring Putin's war home in Russia.  The high risk of nuclear war is already there,  Putin has been rattling that saber for months.  I don't really see how more forcefully opposing him changes that risk,  which will not go away until Putin is dead and gone.  

Sunday, November 20, 2022

Ground Testing Ramjets

This is an expanded version of a posting I made over on LinkedIn 20 November 2022. There is a wordcount limit there,  that I do not have here.

A ramjet comprises air inlets,  a combustor chamber,  a nozzle,  and a fuel supply.  Historically,  these have pushed missiles.  They scoop up air by the ram effect in high-speed flight,  which both raises its pressure,  and raises its temperature. 

There are basically three ways to test such a device on the ground.  The first is the “freejet test”,  which is basically a high-speed wind tunnel with heated air,  in which the entire missile is placed.  This tests for the inlet performance including vehicle attitude effects,  the sized inlet/nozzle balance,  and the efficiency and performance of the combustor.  What is important besides simple supersonic airspeed is the right wind tunnel air temperature so that the air total temperature as captured within the inlet is at the correct value,  same as it would have been in flight at that speed.  A very large quantity of supersonic air must be sent through the wind tunnel,  compared to the quantity of air that the inlets actually capture.  This is the most expensive mode of ground testing.

The second is the “semi-freejet test”,  which is also basically a high-speed wind tunnel test,  in which only the inlets are submerged within the heated supersonic airstreams.  Only the propulsion system (inlets,  combustor,  and nozzle) need be tested.  This tests for the inlet performance excluding vehicle attitude effects,  the sized inlet/nozzle balance,  and the efficiency and performance of the combustor.   The total wind tunnel airstream quantity is large compared to that captured by the inlets,  and it must produce the right total temperature as captured within those inlets.  But the total supersonic air quantity is far less than that of the freejet test.  This is still quite expensive,  but it costs a lot less than a freejet test.

The third is the “direct-connect” (or “connected-pipe”) test,  in which a heated air supply delivers the flight quantity of air,  at the flight total temperature,  to only the subsonic portion of the flight inlets.  This does not test for inlet capture and recovery performance or the vehicle attitude effects upon them,  and it does not test for the sized balance of inlet and nozzle.  It only tests for the efficiency and performance of the combustor,  under the presumption that inlet performance (with vehicle attitude effects) is already known separately.  The quantity of air is only that which would have been captured by the inlets,  at the flight total temperature,  and it is delivered to the inlets contained in piping flowing subsonically,  not as a free supersonic jet.  This is the most economical way to test for combustor efficiency and performance.  The relative effects of fuels,  insulations,  injection schemes,  and materials of construction can also be tested most cost-effectively this way,  as this is the least-expensive test mode,  by far.

---------------------------  only this far on linkedin,  due to wordcount limit

Heating the Air

There are two ways to heat the air that is delivered to the test article in direct-connect testing:  “vitiation” and pebble-bed heaters.  In vitiation,  the airstream gets a gas fuel added to it,  and combusted,  then makeup oxygen gets added back to the stream.  The inert gas in this “vitiated air” stream includes the vitiation combustion products,  not just the nitrogen and argon and trace gases that are in real air.  This requires precise real-time computer control,  to achieve the airflow quantity and total temperature simultaneously,  and still hold the oxygen content to exactly that of air.  That type of control is not cheap.  For some fuels containing reactive metals,  it is not chemically correct:  the carbon dioxide and water vaper combustion products are additional sources of oxygen,  besides the basic oxygen content.  That can lead to massively-erroneous test results,  especially if magnesium is involved!

The pebble bed heater is a large and massive pre-heated bed of particles through which the airstream is percolated,  to heat it up to essentially the pebble bed preheat temperature.  The result is chemically correct air at the pre-heated bed temperature.  This does not require any precise computer control at all,  and so is much,  much less expensive than vitiation,  and it can be used reliably with metallized fuels. 

The airflow can be fed through two lines,  each with its own pebble bed heater at two different pre-heat temperatures,  and then combined into a single mixed stream fed to the test combustor’s inlets.  In this way,  by controlling the two airflows,  a variable mixed temperature can be delivered to the test article,  as well as a variable airflow rate.  This only requires the pre-programming of simple linear controls on the metering venturi pressures,  and can even be done manually,  if exacting precision is not required in the delivered airflow and total temperature.

Pebble bed heaters are usually best done as metal balls pre-heated electrically,  but those will have more severe max temperature limitations than vitiation.  Higher temperatures closer to vitiation capabilities are possible with combustion-gas preheat of the pebble bed,  using rock or ceramic pebbles,  but this risks a dusting problem that can cause erosion of structures downstream.

These testing modes are simply not appropriate for scramjet articles at speeds above about Mach 5 or 6,  as the air heating methods are simply incapable of supplying the necessary extreme temperatures.  The usual limitations correspond with speeds nearer Mach 3 to 4.

Altitude Simulation

There is the issue of open-air nozzle testing versus high altitude simulation.  If the ambient atmospheric pressure is too high,  it will cause shock-separation of the flow in the supersonic portion of the nozzle,  and perhaps even unchoking of its throat.  Using a sonic-only test nozzle profile avoids shock separation at the cost of incorrect nozzle thrust,  but cannot stop unchoke,  if the backpressure is high enough.  Open-air nozzle testing does allow very informative photography. 

For the freejet and semi-freejet test modes,  if the test cabin is sealed,  it is possible to operate the system at a low-enough test cabin pressure so as to maintain the choke or even the full-flowing nozzle of a test article at high-altitude conditions.  The exact pressure corresponding to desired alrtitude is not necessary,  only one such that a choked and full-flowing nozzle is maintained.  Not all such facilities can do this.  If the test cabin is vented to the atmosphere,  then only lower altitude conditions may be tested that correspond to a choked,  full-flowing nozzle.

Direct-connect testing is different.  If the ambient backpressure precludes a choked and full-flowing test nozzle,  then a supersonic diffuser can be installed,  along with an ejector.  This precludes tailpipe flame and plume photography,  but it does allow high-altitude testing in terms of airflow rates and achieved engine pressures.  The diffuser can be sealed to the test article with a rolling diaphragm seal.  Again,  exact backpressure at the nozzle is not required,  only a pressure such that a choked and full-flowing nozzle is maintained.  The diffuser has a supersonic compression convergence,  followed by a friction decelerator at constant area down close to Mach 1,  but not actually subsonic.  This is followed by a divergence in which subsonic shockdown occurs,  followed by a significant degree of subsonic diffusion. 

The subsonic stream at the diffuser outlet will likely not be diffused all the way back up to ambient atmospheric pressure,  so this is coupled to an ejector pump that raises the pressure the rest of the way.  The working fluid for this ejector could be steam from a boiler,  or it could be air from the blowdown air supply that feeds the test article,  since test article air flows are much lower at high altitude,  than they are nearer sea level.   

Performance Determination

Combustor efficiency can be calculated from post-combustion static pressures just before the nozzle entrance (termed station 4),  or from measured thrust calibrated for tare forces,  or both.  Note that both require a choked and full-flowing nozzle,  which is why the backpressure unchoke is to be avoided at all costs.  There is no such thing as a tare pressure,  so if the sources of data disagree on the efficiency,  trust the data derived from static pressure;  you simply do not have your facility tare forces properly calibrated.

For pressure-based performance,  your nozzle entrance contraction ratio and expected combustion gas specific heat ratio provide the ratio of chamber combusted stagnation pressure Pt4 to the measured combusted static pressure P4.  You need to know very precisely the flowrates of air wa and fuel wf and any ablated liner massflow wabl.  Their sum is the total massflow at station 4 w4.  You will also need the value of the discharge coefficient CD at the ramjet throat (station 5),  something determined separately by flow calibration testing.  But for good nozzle designs,  it is never very far from 0.98.

The choked massflow equation determines combusted characteristic velocity c*4 = Pt4 CD A5 gc/w4,  where gc is the gravity constant that makes the units consistent.  The fuel to air ratio,  the inlet total temperature Tt2,  and theoretical thermochemical calculations done at the measured P4 will produce a theoretical combusted characteristic velocity c*o4.  Their ratio is the stream thrust combustion efficiency ηcSA = c*4/c*o4.

For thrust-based performance,  you will need the same estimates of Pt4,  A5,  and specific heat ratio as were used in the pressure-based analysis,  the tare-corrected thrust measurement also corrected for any supersonic diffuser forces (thus being the actual nozzle thrust Fnoz),  the exit area A6,  the half-angle of that exit cone a,  and the ambient or altitude diffuser pressure around the nozzle exit P7.  The nozzle kinetic energy efficiency calculates as ηKE = 0.5*(1 + cos(a)),  where a is simple if a conical nozzle,  or the average of near-throat and exit-lip values,  if a curved bell.  

The nozzle exit ratio A6/A5,  kinetic energy efficiency,   and combustion gas specific heat ratio allow you to compute the vacuum thrust coefficient CFvac by standard ballistic methods.  That plus the values of A6 and P7 allow you to compute the actual thrust coefficient CF.  Then the thrust-effective Pt4 = Fnoz/CF A5.  From there,  the analysis is exactly the same as pressure-based,  all the way to ηcSA.

To meet combustion efficiency definition reporting requirements per the Chemical Propulsion Information Agency (CPIA) standards,  you must convert these stream thrust efficiencies (both bases) to the temperature-rise basis that is considered standard for ramjet work,  where Tot4 is the theoretical combusted total temperature from your thermochemical calculation:  

ηcΔT = (Tot4cSA2 – Tt2)/(Tot4 – Tt2).

Final Comments

I’ve tried to describe the bare bones of testing ramjets on the ground.  There’s a whole lot of nitty-gritty details I left out.  Describing all of that is closer to a book than just an article.  


Wednesday, November 16, 2022

You Are What You Spout

 



For those who haven't guessed,  the named of the file is "Trump horse shit.png".

Update 12-5-2020 add another funny to this.  It is one possibility for dealing with Trump's "Truth Social" platform,  which is anything but truthful. 



Monday, November 14, 2022

Spacecraft Windows For Entry

In response to a request,  I researched how the Apollo spacecraft windows were built,  and did a oversimplified steady-state thermal model “by hand” to evaluate how the outer pane of fused silica fared during entry.  This model assumed the middle of the pane was isothermal at a full equilibrium soakout,  balancing the applied entry convective heating,  with conduction into the supporting structure.  Plasma radiation was not considered.  This was a simple serial thermal resistance model,  with the supporting structure a constant-temperature heat sink.  It was done as a single-point steady-state analysis,  at the max heating point for an Apollo capsule returning from low Earth orbit. 

This is by no means an accurate model!  To do this correctly requires not only a 2-D (or preferably 3-D) finite element heat transfer model,  but also one done with time as a variable,  and with the applied heating rate also variable over that time!  Such is not something I can do “by hand”,  even assisted by a spreadsheet.  The process is fundamentally transient,  while my analysis is steady-state. 

My estimate is thus an over-estimate of the achieved center-of-pane temperature.  That is why the same basic outer window pane design actually survived a direct entry at nearly escape speed,  coming back from the moon.  However,  I did also investigate the trend of pane temperature for the higher convective heating rates associated with attached flow,  instead of the separated wake zone where these Apollo windows were actually located.  The results show the extra heating to be catastrophic.

The entry conditions I analyzed are given in Figure 1.  This was done with the rough-estimated entry analysis given in Reference 1.  The associated rule-of-thumb effective plasma temperature is 6370 K. 

Figure 1 – Apollo Entry Conditions From Low Earth Orbit

The window pane geometry and associated assumptions are given in Figure 2.  This is for only the outer pane of a 3-pane window design used on the Apollo capsule.  That design is described in Reference 2.  I initially tried a 10-inch by 10-inch pane,  but that design proved infeasibly hot.  I did not get feasible pane soak temperatures until I shrank the design to 4-inch by 4-inch size.  Therefore,  smaller exposed window size is a critical variable.

The 2-part silicone adhesive between the fused silica pane and the supporting structure is presumed to be bonded only on the structure side,  and is just in intimate contact (under compression pressure) on the window pane side.  I did not get feasible pane soak temperatures until I reduced the silicone thickness to 0.020 inches from the initial 0.080 inches.  Thus a smaller temperature drop achieved across the mechanical pane retention seal is another critical design variable.  

Figure 2 – Outer Pane Modeling Geometry and Assumptions

The oversimplified thermal resistance model is illustrated in Figure 3,  along with the results I got for the feasible case that became baseline.  I used a couple of worksheets in a spreadsheet to carry out this analysis.  One worksheet converted units to a common basis,  and calculated the necessary cross section areas through which the heat had to flow,  and the lengths down these resistances that it flowed.  The other worksheet ran the actual steady-state thermal resistance model.

The thermal resistance model took the form of a user-input heat flow (heat flux times pane area) through the thermal resistances of the edges of the isothermal pane,  and the thin areas of adhesive on both sides of the pane,  to a constant temperature heat sink of the supporting metal structure.  The details of how the parts bolt together and what the other 2 panes are,  are irrelevant to this oversimplified result. 

That heat flow through each thermal resistance produces a steady-state temperature drop across each resistance.  Adding those drops to the sink temperature is thus a steady-state estimate of the temperature near the center of the window pane,  and also on the pane side of the adhesive. 

Note that I did this in Watt-cm-degree K units,  instead of the Watt-meter-degree K units that are “SI” metric.  This was done merely for convenience,  since the applied heat flux numbers are more conveniently measured in Watts per square cm units. 

The baseline worksheet images are given in Figure 4.

Figure 3 – Oversimplified Steady-State Thermal Resistance Model and Baseline Results

Figure 4 – Images of the Spreadsheet Worksheets Used For the Baseline Case

I accumulated results in the thermal model worksheet for the baseline wake zone heating case,  plus two higher heating rate cases that correspond to attached flow scrubbing the window surface,  just remote from the stagnation point.  Those results are given in Figure 5.  These heat fluxes are factor 2 to 3 below that for the stagnation point,  while the leeside separation wake zone heat flux is factor 10 below stagnation. 

I reported temperatures in degrees C instead of K,  just for convenience.  Note that the 316 C failure temperature for the silicone is actually 600 F,  a well-accepted estimate for that kind of material.

As for the fused silica pane,  that material is amorphous silica,  which is actually a supercooled liquid of enormous viscosity.  It has no actual “meltpoint”,  only a max service temperature (1100 C),  above which it increasingly softens (meaning its viscosity falls ever faster),  ending in a “liquidus temperature” (1715 C),  at which the material flows fast enough under gravity for humans to easily perceive.

Note that the baseline case is barely feasible for a window in a separated wake zone,  while the 2 higher-heating cases corresponding to attached flow are catastrophically higher in temperature!  Not only that,  but the silicone adhesive also overheats for the 2 attached flow cases,  while it is well within its capability for a window in a wake zone.   Thus,  locating exposed windows in a separated wake zone  is utterly critical,  unless they are to be covered during entry by suitable heat shielding materials! 

Figure 5 – Results Obtained for the Baseline Case and 2 Higher-Heating Cases

Conclusions

#1. Do not use these numbers for design purposes!  They must be replaced with 3-D finite element analyses that are time-dependent.  The numbers given here merely identify critical considerations.

#2. It is utterly crucial that any exposed windows be located in a separated-flow wake zone somewhere on the leeside of the spacecraft.  Windows not located in a separation zone are infeasible for survival. 

#3. It is imperative that any exposed window panels be small in dimension.  The heat to be managed is proportional to pane dimension squared,  while the thermal conductances depend linearly on pane dimension,  being proportional to area,  but inversely proportional to conduction path length. 

#4. The temperature drop across the gasket or sealant layer between outer pane and its supporting structure for any exposed window,  needs to be as minimal as possible,  in turn requiring that layer to be quite thin.  This applies to gaskets as well as sealant adhesives.

Final Remarks Applicable to Any Entering Spacecraft Designs

#1. Regarding SpaceX’s “Starship” crewed versions: be sure the proposed window locations actually reside in a reliably-separated wake zone,  or else you must cover those windows with some sort of shield during entry.  There is reason to believe an attached jet flow might run part-way down the leeside dorsal surface,  especially at very high angles of attack.  Such happened with NASA’s Space Shuttle,  as described in Reference 3.  Changes to the Shuttle’s nose shape had no influence on that flow field.

#2. The warning in item 1 applies to all other spacecraft designs featuring windows that are exposed during entry.  These must be located in reliable separated flow zones.

References

#1. G. W. Johnson,  “Back of the Envelope” Entry Model,  published 14 July 2012,  on http://exrocketman.blogspot.com.

#2. O. E. Pigg and S. P. Weiss,  Apollo Experience Report – Spacecraft Structural Windows,  NASA TN D 7439,  September 1973. 

#3. G. W. Johnson,  Evaluations of the SpaceX Starship/Superheavy,  published 15 May 2021 on http://exrocketman.blogspot.com.

 

 


Tuesday, November 1, 2022

Voters Beware!

Update 12-5-2022:  Enough is settled to know that Democrats maintained control of the senate,  but lost their majority in the house.  If it weren't for the high percentage of Trumpist extremists among the Republicans,  we would actually get better government with control of congress divided like this,  which normally forces debate and compromise.  

But the Trumpist extremists prevent that,  preferring instead to be the "party of no",  extremized even further from the original form of that obstructiveness devised by Newt Gingrich some decades ago,  during the Clinton administration.  To give you an idea what their ideology is really like,  their cult leader Trump himself,  wants to suspend parts of the very Constitution that he swore to uphold when he was president. 

Update 11-11-2022:  This election is still too close to call,  4 days after the fact,  in terms of which party controls congress.  The anticipated "red wave" seems to have been neutralized by voters wishing to protect democracy or the rights that courts have stripped.  Encouragingly,  many election-denier candidates lost their races,  with a few notorious exceptions.  Also encouraging,  a few Republicans are now saying in public that it is time for their party to ditch Trump.  True,  but what they really need to do is ditch Trumpism itself,  and all the Trumpists.  

Update 11-5-2022 A version of this appeared as a board of contributors item in the Saturday 11-5-2022 Waco "Tribune Herald".  

I also see the Dept. of Homeland Security and the FBI are warning of violence on election day,  likely directed at candidates,  and election workers;  plus intimidation of people attempting to vote.  You won't see much (if any) of this coming from the left.  It is the far right / alt right that is doing this.  The FBI has already designated them as domestic terrorists.  

So beware!  Take care!  But vote!  And please vote against this stuff!

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I do not understand the surprise at the explosion of misinformation and conspiracy theories about the attack upon Paul Pelosi.  I expected such.  Here is why:

The attack on Gabby Giffords predated the 2015 campaign,  and the attack on Steve Scalise was upon a Republican.  Timing is important to understand what has really been happening,  which is also quite asymmetric.   

It was the 2015 campaign/2016 election that induced much of the far-right/alt-right community to coalesce into the Qanon community by 2017 and adopt Trump as its "fearless leader/deity".  Leader cults are leader cults,  religious or political doesn't matter.  Most of the terrorists we have fought,  for so many years are also leader cults.  So were the Nazis,  the Bolsheviks,  Mao’s red army,  and many more.  They all share the same characteristics,  most definitely including a tendency to become violent.

The election denial,  the anti-semitism,  the hatred of immigrants,  the hatred of Democrats (and non-extreme Republicans) as part of the evil world-controlling cabal,  and the exhortations to violence,  insurrection,  and civil war all come from that far-right/alt-right community online. 

The Russians helped spread this crap during the 2015-2016 campaign,  and both the Russians and the Chinese helped spread it during the 2019-2020 campaign.  

They are still spreading it now.  I just received some propaganda from a friend who became a devout Qanon believer back in 2017.  It traces directly to RT ("Russia Today"),  a known Russian propaganda outlet.  RT was finally (and belatedly) banned from broadcasting in the US a couple of years ago,  along with another Russian propaganda organ "Sputnik".  

There simply is not a large,  extreme,  on-line community on the far-left side.  “Antifa” is a category,  not an organization.  The asymmetry of this is so very clear:  it is not about "fair play for both sides". 

It is actually and verifiably about repeated far-right/alt-right fascist attempts to take over America and install a dictatorship headed by Trump,  or someone much like him. 

Had the secret service agents let Trump go to the Capitol on January 6,  2021,  the insurrection would have gotten much closer to that overthrow than it did,  by way of a presidential martial law declaration.  Trump wanted to help lead the insurrection,  that’s why he was so angry when the secret service took him back to the White House instead.

Fascist dictatorship!  Simple as that!  And just as threatening as it sounds!  It is EXACTLY why Biden and Obama have been saying the things about the Trumpist-dominated GOP that they have been saying. 

And they are quite correct to be saying it!  If you see a candidate who is an election denier,  or who implies acceptance of violence against Democrats,  then you know what that candidate really is.  Vote for another candidate.  Or else sometime soon you may never get to vote again! 

Update 11-5-22 Political Spectrum?         

People talk about the political spectrum as if it were a straight line from the “left”,  through the “center”,  to the “right”.   That’s not the best model for thinking about these things.

A better model is a circle leading from democracies on one side to dictatorships on the other.  There’s a “right wing extremist” nationalist/populist path around to the other side of the circle,  and there is a “left wing extremist” socialist/collectivist path around to that same other side. 


As for the dictatorships on the far side of my circle model,  there’s not a dime’s worth of operational difference between those with “right wing” or “left wing” source roots.  They do the very same ugly things to the people they oppress.   They are damned difficult to get rid of,  too!

Make sure of your facts,  as you cannot make a good decision using bad data.  Be aware that bad data is a really serious problem throughout the western world,  and particularly in the US these days.  Then go vote.  I hope you choose wisely,  so that we can all remain free.

The old adage “Look at what they do,  not what they say!” really does apply here. 

As does another:  “How can you tell when a candidate for office is lying?  His lips are moving”.