The AWACS sale to Saudi Arabia may, if eventually consummated, affect the balance of power in the Middle East. A more immediate question is how the president's Senate victory will affect the balance of institutional power between the White House and Congress in critical foreign policy decisions.

Section 2776 of the Arms Export Control Act, a 1974 amendment that gives either chamber a veto over major sales of military equipment, is but one of some 70 "constraints" (many of them the product of the Vietnam era or its aftermath) that potentially inhibit presidential discretion.

These inhibitions touch nearly every aspect of sensitive foreign assistance, from abortion in other countries to the export of nuclear fuels. They signify--or signified at the time of their adoption--distrust of the "imperial presidency."

The impulse underlying them is no novelty in U.S. history. Congress has been trying, often in silly or untimely ways, to bind presidents for a long time. In the 1930s, we had the Neutrality Acts, which sprang from the curious notion that munitions profiteers and bankers had dragged the United States into World War I and which acted, in the event, to handicap those who were fighting Hitler, Franco and Stalin and to make U.S. involvement in World War II inescapable.

Since World War II, we have had the Bricker amendment, which President Eisenhower managed to defeat, and the War Powers Resolution, which his successors found irresistible. Democrats and Republicans, liberals and conservatives, the right and the left--all have found it expedient to support these modifications of the constitutional compact when whim, anger or historical misconception prompted.

Is the tide beginning to turn? President Reagan's vicory in the AWACS fight could perhaps be read to suggest that, although experience suggests that no president wins so hard a fight without unforeseen political cost to himself.

Indeed, as the ever-provocative Herblock suggested the other day, Ronald Reagan is an unlikely beneficiary of the "your president, right or wrong" argument. Reagan, as much as any oppositionist in recent history, made capital of an unbending attack on major foreign policy initiatives in the Ford and Carter years. No consideration of the possible cost of that opposition to presidential authority gave him pause in the Panama Canal or SALT issues.

To be fair, there is a difference. A presidential candidate who exploits the major foreign policy issues of the day can only criticize and influence. A senator, sworn to constitutional and legislative responsibility, can with his vote actually advance or retard a policy. And in that distinction Herblock's amusing irony breaks down.

The lesson of the AWACS fight, it seems to me, is that in its zeal to bind the executive in a Lilliput's web of tiny strings, Congress is trying to live as usual beyond its institutional means.

Consider the larger contradiction. Because there was a feeling in the mid-1970s that presidential "commitments" (remembering Vietnam) are a treacherous guide in foreign policy, Congress designed dozens of prophylactic vetoes. But when the chips are down, it is precisely the same "commitments" argument (don't paralyze or stultify the president; don't give other nations the idea that a president's promises are hollow) that swings enough wavering senators to prevent the veto! The argument is treacherous of course, but then one-house legislative vetoes in foreign policy are a poor substitute for the careful prior consultation that Congress ought to insist upon. The proper argument--the only one that makes lasting sense, and obviously was paramount in the minds of those who wrote Articles I and II of the Constitution-- is that a coherent foreign policy cannot, and never will, be made by 535 people.

The bruising AWACS struggle suggests both the vanity of the legislative veto and the folly and self-contradiction of the "commitments" argument. But surely the larger lesson is that the legislative and executive functions retain a deep constitutional logic that outlasts and defeats the whims and passions surrounding any set of issues. Why, then, does Congress continue to set these embarrassing traps for itself? Because a madman might make it to the White House? It is doubtful that any such president would long be stayed by a legislative veto, especially when a convenient loophole in the same law allows him to ignore the veto.

In an institutional sense, the AWACS fight is another illustration of our wonderful capacity to reinvent wheels. After this costly reinvention, will Congress now remember the plan?