>I'm afraid they'd start a true war against the USA
I seriously doubt they're dumb enough to try. Desperate enough? Yes But the realyy upper people know that one would quickly fail, just like their civil war would.
Manual for Courts Martial. Available by doing a Google search. Make sure to get a copy from a government website, preferably one that ends in .mil. Take my word for it, it is true.
Incarcerate at GITMO or Diego Garcia, then process in front of military tribunal. Enemy combatants are essentially POW's.
Good fences make for good neighbors.