THE IMMEDIATE RESULT of Anwar Sadat's weekend at Camp David was his agreement to swallow his considerable misgivings and lend himself to the continuing efforts of American diplomacy to get the derailed Egyptian-Israeli political train back on the track, and to bring in Jordan. He did this, evidently, without being assured that Jimmy Carter would either apply heavy new pressure on Israel or deliver important new arms to Egypt. This is evidence at once of Mr. Carter's steadiness in approaching the Middle East and of Mr. Sadat's awareness that there is no responsible alternative to working to the end of the process he himself opened in November.

Any thought that Mr. Carter might have persuaded Mr. Sadat to simmer down a little, however, disappeared at the National Press Club yesterday. Reaching out to the American public, President Sadat contrasted the sweep of his offer to Israel of direct talks, acceptance and neighborly relations, with Israel's hedged counteroffer of civil self-rule in the West Bank (minus the substantial area of Greater Jerusalem) and return of the Sinai (minus the settlements and air bases). His own policy he portrayed as fulfillment "already" of Egypt's part of the peace bargain defined by United Nations Resolution 242. Israel's policy he found thin in substance, tendentious in style, suggestive of "a deliberate attempt to erase the impact of the historic initiative and divest it of its driving spirit."

Well, it was Egypt's day. Israel is currently on the defensive in American public opinion, or so we judge. But the Israelis will have other occasions to explain why they reject the tame Palestinian state "linked with Jordan" that is the Sadat definition of Palestinian "self-determination," and why they won't contemplate alternative Sinai security arrangements more respectful of Egyptian sovereignty and pride. The administration doesn't and, at least for now, shouldn't take sides on such matters, but many American citizens will.

Mr. Sadat was particularly telling, we thought, in his harsh attack on the Israeli policy of continuing to expand and establish settlements in occupied territories. The policy mocks Israel's ostensible devotion to peace. It could well cause the collapse of negotiations, and the responsibility would be Israel's alone. On that point, if not on all others, Mr. Sadat deserves the unequivocal support of the American people and the administration alike.