Speakers at the AIPAC conference will undoubtedly defend the special relationship and warn Washington against putting pressure on Israel. But this short-sighted approach would be a disaster for all sides. In her scheduled address to the conference, Secretary of State Hillary Rodham Clinton should reaffirm the U.S. commitment to Israel's existence but make it crystal clear that Washington will no longer tolerate Israel's self-defeating policy on settlements. She should explain unambiguously that Israel faces a choice: It can end the occupation, embrace a genuine two-state solution, preserve its democratic and Jewish character and remain a cherished U.S. ally. Or it can continue the occupation of the West Bank and the siege of Gaza -- a course that will eventually force it to abandon either its Jewish character or its democratic principles, and jeopardize its standing with its most important partner.