The right to bear arms is a right of last resort. Its the right that protects all others and, as such, it is the _most_ essential right.
As for naming incidents in the last 100 years where armed resistance to the United States government would have been productive or useful, I recommend you look up the forced internment of Japanese Americans during World War 2. I also recommend that you read about the Black Panthers standing up to corrupt Oakland police and marching on government buildings, loaded guns in hand.
You don't have to be a crazy conspiracy theorist or a right-winger to realize the thought that "something like that couldn't happen in America" is naive at best.
edit: I omitted an "n"