I don't like what is happening in the partition of Ukraine, but I don't have any desire to go to war to stop it. And I'm beginning to understand how the Brits and French felt in the 1930s about defending Czechoslovakia from Hitler's demand for partition.
Not true. You’re describing is “raising the stakes.” A bluff is intended to force you to fold without meeting the bet. When you fold, you never know if the guy was bluffing. When you call, all betting is over, and hands are shown.
... And don’t be too understanding of Neville Chamberlain. By the time Hitler invaded the Sudenland, he had bombed the German diet, declared himself dictator, and had rounded up Jews for the concentration camps.