Cyanosuke,
I don't know about any political communities online.
Never looked for one, but thats a great idea. You might be able to find some, but be wary of sites which are actually sustained flame wars.

Pheonix,
I get ya.
You dont have to agree, but you also dont have to respect it.
I feel the same way about those who bash military. I helped defend their right to talk shit and I would do it again.