I think that just by declaring martial law and suspending the Constitution would be cause for rebellion. On April 27, 1861, the writ of habeas corpus was suspended by President Abraham Lincoln in Maryland during the American Civil War. Lincoln did so in response to riots, local militia actions, and the threat that the border slave state of Maryland would secede from the Union, leaving the nation’s capital, Washington, D.C., surrounded by hostile territory. So basically Obama could do something like that as well citing the above.
I cannot shake the conviction of that being exactly what is in his plans as soon as he can find a pretext.