The US constitution offers no helpagainst a government that legally
establishes tyranny but I found the following:

When in the Course of human events it becomes necessary for one people
to dissolve the political bands which have connected them with another
and to assume among the powers of the earth, the separate and equal
station to which the Laws of Nature and of Nature's God entitle them,
a decent respect to the opinions of mankind requires that they should
declare the causes which impel them to the separation.

We hold these truths to be self-evident, that all men are created
equal, that they are endowed by their Creator with certain unalienable
Rights, that among these are Life, Liberty and the pursuit of
Happiness. — That to secure these rights, 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 to abolish
it, and to institute new Government, laying its foundation on such
principles and organizing its powers in such form, as to them shall"
seem most likely to effect their Safety and Happiness."

Note the last sentence. Yup, the Dec. of Ind. takes precedence in
establishing a right to revolt against an Obamanite tyranny if
necessary. Thank God Americans are armed.