The new Reagan administration could be allowed a period of grace before it developed a coherent policy on the Middle East. But after more than a year it is clear that US policy is in a state of drift. The United States and Israel seem to be on a collision course, despite President Reagan's pro-Israeli sentiments. The moderate Arab leaders are dubious about Washington's diplomacy. And, if that were not enough, the policymaking bureaucracy is torn by internal dissension.
Surely it is time for President Reagan to play an active role in Middle East affairs, to put a stop to public feuding between his aides, and to begin to give substance and direction to American policy in the region. The reason is plain: the Mideast remains a volatile area of the world where failure to pursue a peace settlement only adds to the danger of instability and war.
To his credit, the President has accepted the common sense of pursuing a balanced diplomacy that takes account of US interests in Arab as well as Israeli policies. But this diplomacy should be conducted quietly, in dignified fashion, and without needlessly alarming Israel, which rightly perceives that American public opinion has been swinging away from an overwhelming pro-Israeli position. Public remarks made during Defense Secretary Caspar Weinberger's foray into the Middle East -- including the comment that the US is trying to ''redirect'' military policy away from Israel toward the Arabs -- were indiscreet to say the least. They served only to heighten Israeli anxieties. President Reagan and Secretary of State Haig have had to come galloping to the rescue with comforting reassurances to Israel, but it is not easy to erase the damage done.
Of greater concern, however, is the general muddle of present policy. The centerpiece of Reagan diplomacy has been the quest for a so-called ''strategic consensus'' in the Middle East, a kind of anti-Soviet collective security system dictated by the rising importance of oil as well as the growing potential for Soviet expansion. Yet, as Mr. Weinberger found in his talks with the Saudis, the Arabs are less troubled about the Russians and Soviet aggression than about Israel and Israeli aggression. They want a change in US policy toward Israel, a US willingness to press the Begin government to negotiate a just settlement of the Palestinian question. It is doubtful that even the hastily contrived effort to shift the US policy of strategic consensus away from an emphasis on the Soviet factor to one of thwarting ''internal subversion'' will alter the Arab position. To the Arabs, the conflict with Israel is uppermost.