You want to continually blame the United States and its current President for the bad behavior of our erstwhile allies in Europe and elsewhere.

No. We're blaming Trump for his own behavior. Erstwhile is right, because he has betrayed his allies, threatened them, made clear that he's not going to come to their aid when needed, and sided with their enemies.

NATO exists for one purpose, to deter and if necessary counter Russian aggression against Europe. The European forces in place are sufficient for that purpose, as long as they can count on the U.S. and Canada's commitment to the alliance. The U.S. has chosen to have a global military footprint and it spends on defense accordingly. It has a number of (erstwhile?) alliances around the world to help it maintain its footprint, such as Japan, Korea, Australia and NZ in the far east. None of these countries are ever expected to match America's global footprint. The Japanese are not expected to fight in Europe, and the Germans are not expected to fight in Taiwan, if it ever comes to that. So comparing the defense budget of any of those (erstwhile) allies to that of America is a red herring. If you were to calculate America's military capabilities across its global footprint, the way they are actually spread out, you'd find that America's actual financial and material commitment to the defense of Europe is not any larger than the Europeans' themselves.