This was Obama's claim to the Islamists that attended the farcical Summit on Violent Extremism this week.....
Um, I don't think so Mr. President. The first time Islam reared it's ugly head that had anything to do with America was in 1801, and I'm no history buff but I believe the US was founded a little bit before that. At any rate, the Marines stamped Islam back in its dark hole, during the first Barbary War. Muslim pirates along the Barbary Coast, Morocco, Algeria, Tunisa, and Libya, were capturing American merchant ships and holding the men hostage for huge ransoms.
Thomas Jefferson was having none of it and dispatched the Navy/Marines to handle the situation, and handle it they did. So you could argue that Islam played a key role in making permanent the Navy and Marines as part of the US military, but I don't think that's what he's talking about.
I have no idea what Obama is talking about. To my knowledge Islam has played no role in anything productive or useful, anywhere, much less in the foundation of the US. Will his lapdog media friends ask him to mention a contribution of Islam to the fabric of America? Don't hold your breath.