How would sharia law (Islamic law) change American culture? The full answer, of course, requires a thick book - or a weekend visit to Saudi Arabia. A lot of it would involve sexual control of women by men, and I mean the ugly repressive kind of control. Not good.
If you don't have the time for either of those options, check out the video preview of sharia in America here. It's a funny video about a very un-funny reality. For a dose of that reality, see the second video below.