THE PHILIPPINE presidential elections on Friday will mark the first real foreign policy test of the new year. Much is at stake: Access to military bases, stemming a communist insurgency, the political and economic stability of a nation with which the U.S. has a history of friendly relations.

U.S. policy has assumed a clear focus. Wisely eschewing support for any particular candidate, the U.S. is advocating only that the Feb. 7 presidential elections be fair. Using our economic and military assistance programs for leverage, we are pushing for changes that would reduce the role of the government in the economy and break up large, inefficient monopolies in agriculture. We also want military changes that would retire old and corrupt generals while getting the armed forces of the Philippines to adopt tactics and equipment suitable to counterinsurgency.

Current U.S. policy is thus one of conditional support for the current government: providing enough help to encourage reform, maintaining enough distance to encourage moderate opposition forces and avoid alienating the Philippine people.

We need now to look beyond next Friday to the post-election situation. As is often the case, it is easier to begin by pointing out what we should not do:

*Don't pronounce prematurely upon the election. Observers cannot hope to observe what is taking place at the more than 90,000 polling places. More important, they will be unable to observe much of the vote buying or miscounting that is almost certain to occur before and after voting day. In any case, what is needed is not a U.S. verdict on the election (something that would be seen as inappropriate meddling) so much as U.S. sensitivity to the Philippine reaction. We should take our cue from them.

*Don't disengage. We do not have the luxury of simply walking away from the Philippines if politics there are not to our liking. Too much is at stake. When would we re-engage and under what terms? If it is easier to get into wars than it is to get out of them, it is easier to lose influence than it is to regain it.

*Dumping Marcos is an idea that should be dumped. Our experience two decades ago in South Vietnam with with Diem is hardly auspicious. Those in the Philippine army who oppose Marcos (including all of the reform movements) are too weak to do much about it. If we are to signal an interest in a coup in the Philippines, we may find one launched by individuals we would prefer not to see in power in place of the ailing Marcos.

*Outright support of Marcos should be similarly avoided. He has not demonstrated the capacity to undertake needed reforms. His health may give out any day. Why back a man who cannot succeed and may not last if backing him will only alienate the bulk of the people in the country?

*Don't impose sanctions. Aid cuts are a bad idea. Aid reductions would only weaken the economy, further lowering living standards and reducing the government's ability to combat the insurgency. Given the widespread perception in the Philippines that U.S. aid constitutes rent for the bases, aid cuts could result in reduced access to the bases, thereby weakening us militarily while establishing the undesirable precedent that the bases are a political football to be kicked by either side when it is unhappy with the behavior of the other.

*Don't overstate our leverage over Marcos. The U.S. lacks the means to convince Marcos to retire early. We cannot pressure him into doing so, nor will he be bought off with promises of a comfortable retirement and exile as Sen. Bill Bradley (D-N.J.) has suggested. Marcos has too strong a sense of his place in history to be tempted. Perhaps more important, Mrs. Marcos and key cronies have no interest in giving up the prospects of their ruling the Philippines one day.

*Don't gush over the moderate opposition. A victory by Corazon Aquino, even if preferable to a Marcos win, would by no means constitute a panacea for either the Phillippines or ourselves. If her campaign is any guide, Aquino may well lack the experience and savvy to rule effectively. She would face massive economic and military challenges. Her stance on the U.S. bases is equivocal.

What then can we do? Here unfortunately the list is shorter:

*Keep a sense of perspective. Strategic stalemate between government and guerrillas is at least several years off. Time for reform exists; if there is a parallel to Iran here, it is to Iran in 1976, not 1978.

*Work to keep alive a political process after the Feb. 7 election. A Marcos win is probably a foregone conclusion, given his control over the political machinery. Many opposition figures will be dishearterened after the vote, and a good number may even be prepared to head for the hills and join the communists. We should discourage this, instead urging participation in the scheduled May municipal elections. We should also urge calm, pointing out to the opposition that they have no interest in providing a pretext for martial law.

*Keep our eye fixed on the vice presidency. Either Marcos's running mate Arturo Tolentino or opposition candidate "Doy" Laurel (who could win, given the opportunity in the Philippines to split one's ticket in voting) might find himself in a key position should the president's health falter after the election. Working for a proper succession ought to become the number-one priority of the United States.

*Maintain aid at the agreed level, if possible tied even more closely to specific economic and military undertakings. More aid might be offered, but again only if tied to specific reforms.

*Remember that we are the former colonial power. This fact gives us special clout in the Philippines; it also is a source of some resentment. We must be careful that legitimate American involvement in the Philippines does not cross over the line and become unwanted political interference. If it does, we could well find that what limited influence we have in this important country grows even smaller.