Putin has taken the measure of Biden

 Dominic Green:

Is this Biden’s Munich moment? 

It might be something even worse — and the clock is ticking

Actually, it is a bigger deal than Hitler's Munich grab which led to World War II.  Ukraine is a much bigger country with a larger population made vulnerable by a US agreement to protect them if they gave up their nukes.  

Biden's Afghan debacle, in effect, gave Putin the green light to make the land grab.