The only smart people in EU is Poland. After fall of Soviet Union, EU and with it most of East Europe that became EU went for the peace dividend. Cut defense and up social welfare. Poland atleast understand the nature of Germany and Russia. They wisely plan for the worst case scenario in Europe - one massive land war against Poland. Poland is the only nation in EU that maintain her force levels and undergo long term plans to modernize. Everyone in EU probably laughed at her, but they are not laughing now.
Ukrainians must be one of the dumbest people on earth. They have a Russian neighbor that thinks they are still part of Russia and many Russian ethnic transplants put in by Stalin to redress the demographics to insure Russian influence and control. Smart Ukrainian leaders will insure their military is mainly composed of Ukrainian ethnics and never let the Russian ethnics have access to military power. Ukrainian leaders did the worst thing, they skimmed their defense budget and enriched themselves via corruption. Their leaders thought that NATO assurances to protect them and Russia promise to recognize their existance was enough to loot their country for their own gain.
Now we have a broke and unprepard Ukraine begging a deeply in debt US and EU for help. Putin definitely loves the situation. IMHO the Ukraine is a lost cause, redraw the next line of defense for NATO at Baltic states, Poland, Slovakia, Romainia and Turkey. Use the Ukraine conflict as a holding action to buy NATO time to ramp up defense budgets and moving forces eastward.
You may be right. The American security guarantee brings with it moral hazard, such that the countries whose security is tacitly guaranteed slack off and make their defense policy one where they fight any would-be conqueror to the last dead GI. The fall of Ukraine may be necessary to prod both Asian and European countries into spending more money for defense, just in case Uncle Sam decides to sit out an attack on these countries by a foreign invader.