It seems fashionable recently for analysts to leave "why" for future speculation. No one wants to bluntly say that Trump is in Putin's pocket. But that's not really what's important here.

Trump and Putin could hate each other or love each other. What matters is that America and Russia are on the verge of signing a redux of the Hitler/Stalin pact, in which Poland was conquered and divided. One can wonder who bullied whom, or who will be the first to violate it and stab the other in the back. But the point is, these agreements do not happen when either of the parties is a free county. They happen between autocrats.