Israeli Minister Yitzhak Shamir's addition of the Moledet ("Homeland") Party to his right-wing coalition government is meant to strengthen his slim Knesset majority. But it sends the wrong message to the outside world. The party and its leader, Rehavim Zeevi, favor expelling Palestinians from the West Bank and a loyalty test for Israel's Arabs. The idea is winning adherents, although it is not the Shamir government's policy. It runs counter to any hope of peace. Mr. Shamir's disavowal of his new minister-without-portfolio's view is not enough. He should keep the man out of government.