Joan Rivers -- GOES OFF on Epic Israel/Palestine Rant

Joan Rivers jettisoned comedy for politics ... unleashing an impassioned defense of Israel that included an awesome New York/New Jersey analogy.

Rivers was at LAX Thursday afternoon when our photog mentioned Israel and Palestine ... and that's all she wrote.

You gotta see it. It comes from the heart and the gut.

As for Selena's tweet praying for Gaza ... well, see Joan attack.