Summer camp

If you are a young Muslim American and head off to the Middle East for a spell in a fundamentalist “madrassa,” or religious school, Homeland Security will probably greet you at the airport when you return. But if you are an American Jew and you join hundreds of teenagers from Europe and Mexico for an eight-week training course run by the Israel Defense Forces, you can post your picture wearing an Israeli army uniform and holding an automatic weapon on MySpace.