The 2nd amendment isn't important because our government is trying to enslave us today. As a matter of fact, I don't know any sane person that thinks that it is. But over a long period of time, maybe several decades or even several centuries, it isn't unreasonable to think that our freedoms may(not will) have eroded to the point where the only thing we have left to cling to is the right to bear arms.
Realistically, if that did happen, we probably couldn't do much. But with things like that, you gotta at least give it a shot.
My problem with gun control stems from the fact that it doesn't appear to work very well.