To democrats, the only irrefrangible rule is that government must always grow more and more powerful and intrusive.
We call the democrats hypocrites, but they are not, for the reason you cited. Yes, on individual issues, it sounds like hypocrisy, i.e., Bush bombs--he's a war monger, Obama bombs--he's a war hero. But, taken in the framework of "if it furthers the left's agenda, it's good, if it doesn't, it's bad," they are remarkably consistent.