Why do you think there's been so much effort to keep Iran and North Korea out of the nuclear club? Once someone has a high probability of having nuclear weapon and the capacity to deliver it, your tolerable options decline sharply. Russia is the worst-case form of that problem since they have many advanced weapons and even if their maintenance standards have been deplorable the odds are far too high that enough would reach their targets to cause death counts in the range of hundreds of millions.

Yes and this is why the US has been so aggressive about stopping North Korea.

And why the US and especially Israel is so against Iran having nuclear weapons, to the point where Israel would attack Iran militarily, to stop them.

Yes. That's why every tin pot dictator wants nukes.

Hm no that doesn’t sound good either. Alright nuclear annihilation it is! Too bad…

That's the point of sanctions and shipping weapons to Ukraine.

Yup, as long as the tin pot dictator is attacking some country we don't really care about.

Bingo. Unfortunately NATO made it very clear to everyone over the past eight years that it's not going to spill blood over Ukraine.

... But now that the opportunity to trap Putin in a quagmire has presented itself, it does seem to be ready to flood the region with weapons. Had it done so at any point in the preceding eight years, war might well have been avoided.

Which leads me to think that avoiding war was never the goal.

I think it's a bit of a catch-22: given one of Putin's stated aims is to demilitarise Ukraine and remove Western weapons, NATO arming Ukraine earlier would have caused Russia to invade earlier.

Invasions take a lot of preparation. You can't just tell your army to attack some country - they need to plan exactly how they will do it, and practice.

The turnaround time on this sort of thing does not favor the aggressor.