With all due respect to our British friends, I would be very careful of what Churchill wrote. He tended to minimise his errors- and maximise what he would have done.
Read Massie- Dreadnought of Castles of Steel.
(This is not to belittle Churchill- he was the right person in WW2 to lead the UK).
I’m sure that’s true, but logically I can’t think of anything that would indicate Sir Winston’s account of his sentiments as being completely honest for that time and place and in consideration of the event. Whatever the exact opposite of “shitting one’s pants” would be–the feeling that the Japanese and Germans should have had, had they any bloody sense.
The worst case scenario would have been for the United States to have lost all four aircraft carriers it had in the Pacific. To put that into perspective, the United States launched over a hundred aircraft carriers in the next four years.
A Major shares your opinion.
Losing our pacific fleet at sea would have been more damaging from the loss of experienced sailors and officers rather than the material. The Japanese would have found themselves facing a small fleet of Iowas by 1944 and possibly the cancelled successor (Montana class ) instead of the same ships they sunk at Pearl. And of course all the new CV’s we were churning out as well.
I agree about losing the personnel. But even so, they would have been destroying the instruments of the US naval power, not the basis- which was the industrialism and and the capacity of the USA itself- the shipyards, oil installations etc.
Will get off my soapbox now 
Sure, that’s what HE thought, but few people even at the time agreed with him, and it doesn’t make it any less of a mistake just because he rationalized it.
Let’s asssume the Japanese have several advantages: a well-led and -planned attack by surprise against putatively demoralized Soviet forces. My guess is that the large and well-trained Kwantung Army, considered the best of the Japanese troops, would have been stopped cold and mauled.
In the actual event, the 1939 Battle of Khalkhin Gol, the Japanese did not have surprise and were even more roughly handled…their main force was pinned in place, encircled, and completely destroyed.
The Japanese had nothing like the tactics, equipment, philosophy, logistics, and staff work required to take on even second-rate Soviet armored formations. By 1943 the Soviets had the best tanks in the world in huge numbers, and could have handled even a major Japanese effort as an afterthought. That same year they confronted and destroyed Germany’s ultimate offensive at Kursk.
For all the crap wargame designers have written about Soviet unit quality, an experienced German field commander assessed them roughly thus (I’m paraphrasing from memory): “From the start, the Soviets were first-class fighters…in time, they became first-class soldiers.” And there were many of them, well-equipped with rockets and artillery and the world’s best mechanized forces.
Sure they had trouble with German mobility, high-quality German armor and optics, and the military philosophy of the German General Staff. The Japanese had nothing like any of that.
Sailboat
Try
It’s a great place to post “what if” questions and it’s full of people around the world so you get a lot of European perspectives too
That works in Risk, but not so much in the real world. If you’re staging from Greenland you’re going to invade what? Goose Bay, Labrador? Well, on the plus side there won’t be a lot of fixed defences to oppose your amphibious landing, and you’ll score a decent airfield immediately. On the minus side, you now have 1500km of wilderness with virtually no roads before you get to Quebec City. Good luck with that. Northern Canada makes Russia west of the Urals look small. The logistics are beyond hopeless.
Here’s a 1981 paper on that battle by the Combat Studies Institute. A very interesting account.
ETA: I just noticed that the wiki link already references that paper rather heavily.