No, the Second Amendment was most certainly NOT created to permit armed insurrection. Its primary purpose was to permit Americans in border regions to protect themselves from attacks by Native Americans; its secondary purpose was to permit the use of militias in larger wars.
And no, you are quite wrong in claiming that nobody objected to the federal actions in Portland. Perhaps you don't get much news from Portland where you live, but around here we have seen quite a few protests lodged against these actions as well as formal demands from city and state officials that the feds leave. And in fact, the feds have kept a low profile in the last few days.
"You guys talk a good tune…."
At least I know what I'm talking about.