Forgive me if this offends anyone: I've noticed a stereotypical & self-deprecating trend with Jewish comedians. Why is this so common with these comedians?

Think of it this way ... If you can't laugh at yourself, who CAN you laugh at?

Put another way ... If you can't make fun of yourself, you shouldn't make fun of others.

:: This concept also applies to hateful language.  If you can call yourself or your group a "hateful" term - others should be able to, as well ::