As I mentioned in the other comment, Islam the faith and Islam the political system are largely different. Most Muslims (myself included) know a lot about the faith but know nothing about the jurisprudence. So I agree that Islamic jurisprudence is unlikely able to cohabit with American democracy, its pointless to talk about because no Muslim running for public office is trying to introduce such concepts into American politics.
If they're not trying, it's because it would fail due to lack of "faithist" Muslims to support them. Islamist politicians do push for that when they have popular support, and they do have popular support in Muslim majority countries, as well as local areas in other countries. The average Pakistani might not know much about that jurisprudence thing, but the law still prohibits him from having gay sex or insulting Mohammed.
Where are all the secular Muslim countries? Turkey? Why are they so few and so weakly secular?