Putin may be testing just how far he can go. he is already strangling ukraine's economy. he is taking bites out of their territory. and so what happens next may determine how far he goes. what he knows is two clear things: no country in the world is going to send troops to defend his country, and that all of these sanctions hurt european economies, and there's also bite-back here at home with the united states. president biden is already dealing with inflation at a 40-year high, and now oil is trading at $100 a barrel. >> o'donnell: he brought up that several times today, pain at the pump as h...