In 1848, Abraham Lincoln said:
"Any people anywhere, being inclined and having the power, have the right to rise up and shake off the existing government and form a new one that suits them better. This is a most valuable, a most sacred right — a right which we hope and believe is to liberate the world."
And in the Declaration of Independence:
"...Governments are instituted among Men, deriving their just powers from the consent of the governed, that whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or abolish it, and institute new Government..."