Sharia is not compatible with the intentions, thinking and spirit of the Founders. This why Jefferson sent marines to the shores of Tripoli. Obama lies again when he says Islam was involved in establishing US independence unless negatives mean positives. Of course the way he tells lies sucks in many shallow people.
I think the Oath of Allegiance should be modified to include renunciation of all allegiance and fidelity to legal systems incompatible with the American system of government.