First of all if US invades Russia, US will lose.
With that said... US military are better in both quality and quantity than Russia and China and would probably win any conventional war outside Russia.
But on more individual level, an average Ukrainian soldier is obviously better and more experienced than an American soldier. They operated in conditions where an american soldier would simple refuse to fight, further more they actually fought a super power and not guys in pyjamas with rusty AKs and IQ of 67.
EDIT: here is a long post i made in another thread that is kind of relevant to the topic although it is a little OT too...
Science does not work when it comes to Russia, war is far more unpredictable than one can imagen, thought i understand that one needs some kind of way to determine and measure the outcome, it is just that Russia is not an equation, all determinism is thrown out of the window when one invades Russia because Russians win on spirit and will and never because of their superior tactics, in other words when you cross Russian border suddenly 2+2=908356 and military science becomes gender studies or something.
Regarding Mongols i already answered that above to the Shemale poster.
Now when it comes to German invasion there are actually 3 ways of looking at it.
The Western Way: Soviets won because of winter, Lend-Lease and because Hitler did X but he should have done Y.
The Soviet Way: We faced the greatest enemy the world have ever seen and we won. Huge loses you say??? STFU and off to Gulag with you.
The Forest and not the Tree Way: yes i just pulled this name out of my ass
This is where we look at German invasion in a more broader historical/philosophical perspective. I believe it is more objective way of looking at it. I will keep it short although one can write a whole book about that.
So in short: Germany was invading a backward shithole country that just lost million upon millions (let that sink in...
MILLIONS of PEOPLE just in 20 years or so) of people do to WW1, Civil War, Starvation, Repressions and Emigration, further more Soviet Union was scientifically backwards, i mean look at Lysenkoism. We are not done yet, military Soviet Union was 2/10 just look at the failure of Winter War.
So all in all we got a shithole country, with shit economy (communism does not work), shit military, with shitty culturally bankrupt people (homosovieticus culture was shit)... and to top all that this big pile of shit had shitty times for the last 20 years.
What is the logical conclusion here? What would any respectable military commander/scientists conclude?
That`s right he would conclude:
and that would be logical conclusion! When the Germans invaded in summer (there is no better time to invade Russia) they had their conformation bias because Soviet performed terrible, AFAIK most Soviet loses and POWS came in the first year of invasion. Basically the Soviets did almost everything wrong during the war.
Again everything is logical and according to military science.
But then what happens! Stalin gives his speech before battle of Moscow where he awaking the Russian spirit and will. He calls to Russian ancestors not to the shitty cowardly jewish Bolshevik heroes although he did mention Lenin i give you that...
yeah i know Lenin was a probably a finn and not jewish.
Comrades, men of the Red Army and Red Navy, commanders and political instructors, men and women guerillas, the whole world is looking to you as the force capable of destroying the plundering hordes of German invaders. The enslaved peoples of Europe who have fallen under the yoke of the German invaders look to you as their liberators. A great liberating mission has fallen to your lot. Be worthy of this mission! The war you are waging is a war of liberation, a just war. Let the manly images of our great ancestors—Alexander Nevsky, Dimitry Donskoy, Kuzma Minin, Dimitry Pozharsky, Alexander Suvorov and Mikhail Kutuzov—inspire you in this war! May the victorious banner of the great Lenin be your lodestar!
For the complete destruction of the German invaders!
Death to the German invaders!
Long live our glorious Motherland, her liberty and her independence!
Under the banner of Lenin, forward to victory!
We all know what happened after that! Russia conquers half of Europe, send the first man into space and becomes a super power. BTW this happens after 30 million Soviet people died in WW2 and Western Part of Russia was mostly destroyed.
If you still dont see that Russians are successful on will and spirit alone, i dont know what to tell you. BTW i was a hardcore militant atheist so i know how this can sound.
Ivan Solonevich (picture below) one of the greatest Russians that ever lived, actually was advising Nazis because he hated Soviets. He told them not to invade Russia because they would fail. But their were like "Nah man we will because muh military science and logic yo!!!"
Lastly all i can say is i personally like Americans and US, i actually would rather deal with Americans than Russians, i also like your jewish Hollywood and american inventions.
The fact that Trump won the election regardless of media brainwashing and overall political climate in US is indeed tells me something about American people, and that is that you are not only free in actions but also in thought, well at least the right leaning americans are. So i am all for being friends and working together
EDIT: I advice people to watch this movie it kind of relevant to the subject. The movie got English subtitles and all.