The alternative is a new nuclear arms race. Look at it from the POV of neighbors of China and Russia if UN and NATO backs down from nuclear blackmail. In that w

The alternative is a new nuclear arms race. Look at it from the POV of neighbors of China and Russia if UN and NATO backs down from nuclear blackmail. In that world security guarantees mean nothing. If a nuclear power invades you - the world leaves you to die. The only chance to survive is to build your own nukes. Fast forward a few decades and you have like 50 countries with nukes. Good luck maintaining peace then. The problem with appeasement is that people ignore the alternative costs. It always looks good when you assume only your actions have consequences. But inaction also have consequences - you can't just assume status quo remains when you do nothing.