NO SINGLE word has been hotter longer in the Middle East than "homeland," as applied to the efforts first of Jews and then of Palestinians to claim a place of their own. So historically and emotionally freighted is the word that it is difficult to imagine that President Reagan, given as he is to casual statement, could have misused it the other day. "We can't go on with (the Palestinian) people in not providing something in the nature of a homeland," he said, adding: "On the other hand, no one has ever advocated creating a nation."

It seems clear what the president has in mind. His strategy in dealing with the Arab-Israeli conflict centers on drawing King Hussein to the peace table to speak with Israel for Jordanians and Palestinians alike. The formulation "something in the nature of a homeland," as inadequate as it is to all-or-nothing nationalists, represents a ratcheting of the Reagan commitment and is obviously meant to give the king the extra edge of word and hope he needs to take that momentous step to the table. Yet for the United States to offer Palestinians statehood would, among other things, break repeated American vows to Israel and ensure an instant Israeli foreclosure of any talks. Hence the president's hasty balancing assurance to Israel: "no one"--meaning presumably no one in his administration--"has ever advocated creating a nation."

Whether Mr. Reagan's readiness to meet Palestinian nationalism halfway will help lure the wary Hussein may be known in the next few weeks. It is not the president's only contribution to that end. He is stepping up his calculated expressions of impatience at Israel's pace and style in its negotiations with Lebanon, and endorsing the Lebanese aim of ending the occupation rather than the Israeli aim of creating a new political tie. As an inducement and alibi-shredder for Israel, moreover, he pledges to "guarantee" Israel's northern border, if the Israelis will quickly remove their troops, by putting Americans into a multinational force on the border until Lebanon can take over the job. His idea is not simply to relieve Lebanon but to give King Hussein a further demonstration of American seriousness.

The prospects in Lebanon are not altogether bleak. The Lebanese are prepared to go a long way to accommodate Israeli security requirements. Ariel Sharon, with his special personal investment in the Lebanon war, is gone from the Israeli defense ministry. The Americans are pushing. A staged withdrawal remains conceivable.

The prospects on the Palestinian side are another matter. It is perhaps a plus that the PLO, made impotent militarily by the Israelis, has rendered itself impotent politically. That gives King Hussein and his natural Palestinian partners, the more pragmatic West Bankers, a wider opening. The closer he comes to talks, however, the tougher Israel's resistance may be. The Begin government insists it will negotiate only in the old Camp David framework, not in the revised Reagan framework of Sept. 1. Mr. Reagan had thought to revive Israel's Labor opposition by his peace plan, but Labor may be slipping both in its dedication to territorial compromise and in the possibility of its return to power. Arab moderates are torn between urging the administration to put the squeeze on Israel and fearing that the administration will try and fail.

We think Mr. Reagan is right to move toward making good on his Sept. 1 plan. Presumably, he is under no illusions as to the difficulties that lie ahead.