[Irontank]

One American politician who apparently did believe in the right of secession was one Abraham Lincoln...at least he did in 1848

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 and most sacred right, a right which we hope and believe is to liberate the world.
--Abraham Lincoln speech in the US House of Representatives in 1848

[Non-Sequitur]

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.

Sounds more like Lincoln's talking about an inherent right to rebellion.