Bad news is that US is not seen as a good security guarantor and most Ukrainians expect Russia will attack again if there are not strong security guarantees.

There are disagreements within my group on that. I'm convinced World War III began a long time ago, it just doesn't all happen through rolling tanks and buzzing drones.

Collective security is an absolutely wonderful idea. Europe is now deciding that Russia is actively trying to expand the war in Ukraine so that it includes them. Ho exactly does collective security work in that case?