It's all based on a simple belief system - that the ends justify the means. When that's all that matters, hypocrisy is unimportant. The ends are all that matter after all. How you get there is unimportant. When the obtaining and keeping of power is most important (the ends), then you can compartmentalize everything so that you don't have to be bothered by contradiction. It comes down to the ends justifying the means. Never trust anyone who lives by that creed.