Against his will, his instinct and a lifetime of emotional support for Israel, President Reagan is reappraising the U.S.-Israel connection to preserve his "strategic consensus" in the Middle East against Soviet pentration.

The president is deciding whether to impose serious restraints on Prime Minister Menachem Begin's use of U.S. arms. The importance and difficulty of this provoked one high U.S. policy-maker to use uncharacteristically harsh language in privately describing the situation to us: "We don't know how to bring Begin to heel, but we're trying to find out."

It is not easy. Ronald Reagan is just one more preisdent unable to tailor Israeli policies to prevent wrecking U.S. interests in the region. But Reagan's credentials as a card-carrying supporter of the Jewish state is an advantage Jimmy Carter never enjoyed.

Administration officials urging Reagan to get tough were heartened by telephone calls, telegrams and letters praising the president for holding up those F16 aircraft slated for delivery to Israel July 21. Richard Wirthlin, Reagan's public opinion analyst, is now conducting a poll expected to give Reagan high marks for that decision.

This gives him a political basis for addressing the principal problem posed by Begin's free-wheeling use of American weapons: the administration's "strategic consensus" for a U.S.-Arab-Israeli consortium to defend against Soviet designs is being destroyed by Israel's policy.

When Secretary of State Alexander Haig made the rounds of Arab capitals last spring, he pushed that Reagan strategy hard and was offered some help. But moderate Arab leaders said they considered Israel that real threat in the short run.

After that trip, Haig believed he had made progress with the Arab skeptics. But when Israel attacked Irag's nuclear research facility on June 7 and a month later sent its U.S.-supplied aircraft against Palestinian terrorists in a densely populated residential district in Beirut, the Reagan-Haig "strategic consensus" was critically wounded.

Some presidential intimates have cautioned Reagan that the timing of Begin's air raid may have been deliberately planned to weaken U.S. ties with its essential Arab allies -- particularly Saudi Arabia. He has listened closely. One such adviser told us Reagan now agreed "that Begin is making it very difficult to help Israel."

The real impact inside the Arab world of recent Israeli activity is still unclear. In contrast to dire warnings in government-controlled media that the United States is responsible for what Begin does with American-supplied aircraft, Arab leaders are sophisticated; few accept that line.

Still, there are ominous portents. King Hussein of Jordan, a country regarded by Reagan as crucial to the West Bank peace efforts Haig is about to launch, sent a secret message to Washington last week warning that U.S.-Jordanian relations are "at a watershed." The Saudis, who have played a vital backstage role in trying to defuse the Israeli-Syrian missile crisis and act as American agents with the Palestine Liberation Organization, are endangered among fellow Arabs by their pro-U.S. stand.

The Saudis know that Israel has sent its warplanes on illegal flights over their military base at Tobuk on several occasions. By Begin's own definition, all Saudi military power represents a threat to Israeli security. The Saudis ask: What would the United States do if Israel bombed Tobuk as Baghdad and Beirut have been bombed?

The underming of Reagan's "strategic consensus" against the Soviet Union has progressed for the past seven weeks by virtue of Israel's military might. But the administration still considers it the best hope for a Mideast policy to safeguard the Persian Gulf east to Pakistan and south to the Indian Ocean. Reagan is not about to give it up.

To revive their strategy, Reagan and Haig must find some way to control Begin's use of power in the Arab world. Refusing to ship the F16s is the beginning -- the first time the United States has ever blocked military shipments for Israel that actually were in the pipeline. It suggest that more steps will be taken.

Difficult though it is for any president to crack down on Israel and particularly for this old friend of Israel, Reagan has an extraordinary breadth of public support to confront Begin. There is no desire or reason to punish Israel but only to make clear that the American superpower has its own interests in the Mideast that it must pursue for its own sake and ultimately for Israel's as well.