[irv]

The lefties get angry when they are out of power because they believe that it is their ordained place to rule over us out here who are too stupid to know what is good for us.

Makes sense. Now explain why they are so angry when they're in power.

[RebelBanker]

Only thing I can figure is that we the sheeple just will not STFU and follow along the way we are supposed to. Either that or they are upset that their economic and social policies really do not work, which kind of ties in with the first point come to think of it...