Preemptively getting involved in wars that don’t concern us isn’t a takeaway from world war ii. The circumstances that caused that were the result of 300 years of the Westphalian system, and are quite unique.
It might not be your takeaway but it sure is mine. All that stuff with Austria and Czechoslovakia didn’t concern us, until it did. Putting a stop to those shenanigans would have been a million times easier if done early.
You'd be involved in a million times more war. There are too many conflicts for that sort of thinking to work.
The lessons from WW1/2 were (1) don't be involved in the first few years of a World War, they are empire wreckers and (2) after a war, winners should invest in the economic success of the losers and (3) more Bismarck. Being even more aggressive would hardly have helped, the Europeans were all aggressive. Turns out aggression as a strategy led to ... more and bigger wars. Who'd a thunk it.
I was careful to say “strong aggressors.” You don’t need to go after every tinpot dictator who decides to pull something stupid. But something like Russia conquering bits of their neighbors should have been stopped early.
Europeans didn’t get aggressive with Germany until they invaded France, at which point it was too late to bring things to a conclusion without years of fighting and tens of millions killed. A stronger response to anything up to and including the invasion of Poland could have averted the catastrophe.
> But something like Russia conquering bits of their neighbors should have been stopped early.
So would it be fair to say that your WWII lesson is leading you to suggest escalating a war with a major nuclear power as the proper path forward? Because that should be setting off alarm bells that you learned the wrong lesson.
You can see in the world's reaction to the 2003 Iraq invasion; the correct response is no escalation and let the government of the defending country get pancaked. The damage is kept to a reasonable minimum and then some attempt can be made to put civilisation back together again. A China or a Russia going in to escalate the conflict or trying to stop the aggressors would have been a disaster for everyone. We could have had something as bad or worse than the Ukraine war 20 years earlier.
The US has been pouring military aid into Ukraine since 2014 and the net result is that the Russian army mobilised and despite terrible losses is marching across Ukraine. If the US had poured more resources in, the mobilisation would only have happened faster.
The chain of events you seem to be suggesting is something like Russia has good relations with their neighbour, then that neighbour's government collapses in a highly suspicious coup and then, presumably, the US military starts to overtly move in and set up military bases. If you think that is the path to peace I'm not sure what lessons to even try to draw from WWII, it doesn't look comparable to me apart from a common thread of strategic lunacy. But it is remarkably aggressive and would just have accelerated the timeline for Russia's invasion. I don't know what you expect Russia would do, but given their actual response to NATO's involvement in Ukraine it would be aggressive and undiplomatic if NATO had been more visibly involved.
I suppose we wouldn't have to worry about escalating to nukes today, since we'd have answered that question some time in the 2010s and the rivers of blood shed would be congealing by now.