What would Trump do, if Putin invaded Western NATO allies, sending tanks through Western Europe?

Why is the Democratic Party in the United States becoming more and more like the Communist Party of the United States? It has degenerated from a center-right party to a left-wing party and continues to move in a far-left direction dangerously.
What is Hillary Clinton's history with the White House, and why do you think she criticized the move to tear down part of the White House for a new ballroom by calling it "your house"?