There are fewer of these damned if you do, damned if you don’t dilemmas today than there were during the Cold War. Russia does not have massive conventional forces parked permanently across the border from the Baltic states, Poland, etc., threatening invasion. It can’t afford that.

There is time for these countries and their NATO allies to put in place a conventional deterrent force (tanks, planes, troops) when it appears that Russia is placing a conventional threat across the border.

(That is all happening today)