ON THE NORTHERN Philippine island of Luzon, some 50 miles from Manila, stand two symbols of American Pacific power: the Navy's base at Subic Bay and the Air Force's Clark Air Base, two of the largest U.S. overseas bases. With the U.S.-Philippine 1951 Mutual Defense Treaty, they represent a major U.S. military commitment.

The Navy and Air Force are strongly wed to these bases, and the Pentagon offers many reasons why they should be kept. However, Congress recently has tended to question their strategic value and their political and financial costs. For some members of Congress, the mystique of Filipino-American brotherhood has been shattered as much by Philippine President Ferdinand E. Marcos' demands for a large payment of rent for the bases as by his destruction of the semi-democratic system they regarded as an American legacy to his country.

A modified agreement governing U.S. use of the bases was signed by Marcos in 1966. This was to run until 1991, with neither party having the right to alter its terms without the concurrence of the other.

However, since his proclamation of martial law in 1972 and his assumption of virtually dictatorial powers, Marcos has been demanding that the agreement be renegotiated to provide further Filipino control and a rental of well over $1 billion for a five-year period.

At the same time, Marcos expects the United States to honor its commitment to maintain the security mantle provided by the 1951 treaty -- insisting this be broadened to provide firmer assurance of U.S. backing for his oil claims in the South China Sea.

The Carter administration has been involved in the same "delicate negotiations" for a new base agreement that Henry Kissinger got off to such a disastrous start. In December 1976, Kissinger yielded to Marcos' demands for rent and offered $1 billion in military and economic aid over a five-year period. Marcos turned down the offer. Apparently he believed that a new administration might give him more.

But the Kissinger formula remains attractive to the Philippine leader because its one-shot transfer of funds bypasses potentially hostile yearly congressional scrutiny and leaves him in a financial position to buy arms from the United States. As the recently retired chairman of the Joint Chiefs of Staff, Adm. Thomas H. Moorer, acknowledged last year, "Rent from the bases -- which more than likely will be in excess of $1 billion for a five-year period -- will ensure Marcos a continued source of hard American currency should the Carter administration reduce aid in reaction to the alleged human rights violations of the Marcos regime."

Marcos has been doing well in his dealings with the present administration. Military aid has remained approximately the same as under Ford, and economic assistance has been significantly increased. Rather than refusing to pay additional compensation to keep the bases open and insisting upon adherence to the existing agreement, the assistant secretary of state for East Asian affairs, Richard Holbrooke, has secured presidential backing for picking up where Kissinger left off. The administration has mollified Marcos by a variant of Kissinger's proposal that provides for a large amount of annually appropriated economic support that need not be identified as rental for the bases. If Congress refuses to approve this increased aid, payment can be channeled through the International Monetary Fund, World Bank or other international agency where the administration's influence remains heavy and largely outside congressional control.

Whether remuneration to Marcos is called "rent" or by some euphemism more acceptable to Congress, the Philippines becomes the only country with which we have a mutual defense treaty that obliges us to pay for using local base facilities that serve the security needs of both countries. The costs of the bases have been borne by the United States, with wages and other U.S. expenditures bringing into the Philippines economy around $200 million a year. Beyond this, U.S. military personnel spend at least $50 million more.

Moreover, Marcos' demand for rent raises a serious question of precedent. We also have mutual defense treaties with Japan and South Korea, where we likewise have base facilities. If the United States pays rent to Marcos, why shouldn't these other countries exact rent?

Some knowledgeable officials believe that Marcos calculates he is better off with a publicly unresolved base dispute, and that he may continue making demands that he realizes the United States will not accept. This not only provides him with sustained leverage for exacting aid from Washington, but also helps give him the public image of a man willing to stand up to the United States. This is politically useful, both domestically and in his efforts to become a Third World leader.

Americans clearly have been misled as to the actual value of the bases and the 1951 Mutual Defense Treaty. Though for the Navy and the Air Force the bases are comfortable and convenient, they are no longer of fundamental importance to U.S. security. Indeed, our continuing occupation of them, together with certain features of the interrelated treaty, put some U.S. defense interests distinctly at hazard. There are strong arguments for positioning U.S. air and naval facilities elsewhere in the western Pacific and for either terminating the defense treaty or rewriting it. Human Rights Concerns

WHILE UNSURE as to their actual strategic value to the United States -- and afraid to challenge Pentagon experts on this issue -- many in Congress are dragging their heels on assistance because of Marcos' martial law. Their concern was not assuaged when the Department of State acknowledged last February that "no real steps have yet been taken toward the restoration of democratic government or the elimination of the more severe intrusions on individual rights," and said it had no reason to doubt the authenticity of continuing reports of human torture.

In April, Marcos staged a blatantly fraudulent election for what is actually a powerless legislative assembly. This was calculated to reduce congressional criticism by demonstrating that Marcos was moving back toward democracy. U.S. officials also believed that establishment of such an assembly would undercut congressional fears that any new base agreement might not endure after Marcos left office because while this new body might be Marcos' puppet, its endorsement would endow the agreement with a legitimacy that would continue beyond his death or loss of office.

But the nature of this "election" and the arrest of many of those who ran against Marcos' slate ensured that this maneuver would backfire. Congressional outrage was demonstrated in a letter drafted by the sober and respected Iowan, Berkeley Bedell, and signed by 114 members of the House. Expressing concern over violations of human rights, and shock at the conduct of the election and the arrests of opposition candidates, its signers made clear that their support for continued U.S. aid would be dependent upon "meaningful efforts to redress this situation."

Since then congressional disapproval has been less vocal, with many members bowing before the administration's arguments that criticism should be curbed lest it jeopardize U.S. base rights. The Internal Threat

PROPONENTS OF of the bases now rarely argue that they are necessary to defend the Philippines under the Mutual Defense Treaty, for clearly adequate measures could be mounted from U.S. facilities outside the islands. The U.S. military privately acknowledges that there is no credible Soviet or Chinese threat to the Philippines, and it is evident that if either country were to try an air or naval assault, American power based in Japan and Guam could easily interdict the effort.

The only real threat to a Philippine government, it is widely agreed, is internal. Because of this and the ambiguity of the U.S. commitment under the Mutual Defense Treaty, any responsible discussion of keeping a U.S. military presence in the islands requires a close scrutiny of both the terms of this treaty, with their differing American and Philippine interpretations, and the political context within which it must operate. It is here that the Carter administration has been most complacent.

Both Subic and Clark are located near traditional centers of insurgent activity. The major insurgent force, the Maoistoriented New People's Army, with 2,500 to 3,000 armed men, is still much smaller than its earlier counterpart, the formidable Hukbalahap, which in the early 1950s was strong enough to penetrate the suburbs of Manila. The NPA, however, is growing, and its emphasis upon building cadre, developing better rapport with peasants and acquiring weapons (mostly purchased surreptitiously from Filipino soldiers) rather than military confrontation gives a misleading impression of its potential capabilities.

Certainly the mounting economic disparities, the lack of progress with agrarian reform, the frequent brutality of the military and dissatisfaction with martial law provide increasing political capital for almost any opposition leadership. The possibility of increased insurgent activity adjacent to the bases is taken very seriously by some senior U.S. military officers.

With about 85 percent of the government's combat troops trying to suppress the rebellion by Filipino Moslems in the southern islands of Mindanao and Sulu or committed to garrison duty in the Spratley Islands, where many believe oil will be found, virtually no reserves are available to confront a serious increase in rebel activity in Luzon.

Nor should one overestimate the capacity of the Philippine military. Although their numbers have increased 300 percent since 1972, they have been able to achieve no more than a standoff with the Moslem insurgents, despite an enormous superiority in firepower.

Philippine military protection of the U.S. bases is not impressive. Several thousand impoverished peasant squatters have moved into Clark Air Base, and some are believed to have ties with the New People's Army. The fences around Clark and Subic are never fully intact, for there is a thriving black market industry in selling them for scrap.

Since the Carter administration has done nothing to disengage from the still operative Manila Pact -- the centerpiece of the old SEATO -- the United States is bound to come to the support of either the Philippines or Thailand in case of external aggression. If their governments should be under serious threat from rebellion, presumably neither the present administration nor Congress would be disposed to accept the tortuous interpretation of th pact's language that permitted the Johnson and Nixon administrations to employ it to send troops to fight an insurgency in Vietnam. Nor probably would they countenance interpretation of the U.S.-Philippine Mutual Defense Treaty as extending that commitment to countering a rebellion.

However, the existence of the Philippine bases provides something of a tripwire for American military intervention. Any American president would find it difficult not to order military measures against Philippine insurgents if they threatened military and civilian base personnel. It would be quite simple for Filipino insurgents to provoke an American military involvement that might be politically beneficial to them because of Philippine nationalist reaction.

A much more immediate danger is posed by the recent occupation of islets in the Reed Bank area of the Spratley Islands in the South China Sea some 250 miles west of Manila. These islands constitute a disputed area of overlapping claims by the Peking, Taipei, Hanoi and MAnila governments, with the last three maintaining garrisons. The islet occupied by the Filipino troops is 200 yards from one garrisoned by the Vietnamese, whose claim has been inherited from that of the U.S.-supported Thieu government in South Vietnam. The reason for these expensive occupations is oil, believed to lie in the shallow seas surrounding the islets. Manila has already engaged at least one American firm in exploratory drilling, despite the efforts of the U.S. Embassy to discourage this.

Gen. Freddie Poston, commander of the 13th Air Force at Clark Air Base, told me, "An oil strike in the Spratleys could precipitate a dangerous situation." The Filipinos have very firm expectation of U.S. support if they get into trouble with the other claimants, and Gen. Poston has been under constant pressure from the Philippine military to put his planes on a standby alert to meet this contingency. So far he has refused.

This dangerous situation is not defused by our Manila Embassy's reiteration that the United States does not regard the Mutual Defense Treaty as applying to the Spratleys. The Filipinos insist that the treaty does cover them there. The treaty was drawn up during the Korean War when it was to the American interest that it cover our forces throughout the Pacific, and it is this language that has come back to haunt us. For its reciprocal Philippine protection extends not merely to attack against the Philippines themselves but also to Filipino "armed forces, public vessels or aircraft in the Pacific." It is difficult to argue that if its provisions once covered Philippine-based operations of U.S. troops in Korea and later Vietnam (where SEATO was also invoked), it should not today cover a Philippine garrison in the Spratleys and supply ships and planes.

Because of heavy dependence on foreign oil, Marcos and his military leaders are intent upon holding onto and developing their Spratley claim. What if Marcos or a successor gets into serious trouble in the Spratleys and we don't use the air and naval we have beased at Clark and Subic to bail him out? Philippine nationalist sentiment would be outraged and probably no government could successfully resist the demand that we be ousted from the bases. Would the United States then have any alternative to withdrawal? The only answer one top military official could give me was: "Well if they didn't want us here, we'd have to leave." Keeping the Political Status Quo

KEEPING the American presence in the Philippines also draws the United States into the political arena in a way that heavily influences Philippine policies. We must support the government in power. This was perceived in the Senate's 1969 hearings by Sen. J. W. Fulbright, who observed that, because of our interest in the bases, "We will always resist any serious change in political and social structure of the Philippine government, which is very likely to be, in the long run, a detriment to the people of the Philippines." Thus, so long as the United States is intent upon keeping the bases, it will act to preserve the political status quo, even if that means support of Marcos' martial law regime.

Americans who have believed that it is traditional for this country to encourage democratic government may find it incongruous that U.S. military and economic assistance markedly increased in 1972 after Marcos proclaimed martial law. This year, the Carter administration is seeking the same $37.3 million in arms aid that was provided last year. This military support tells Filipinos that the United States stands four-square behind Marcos.

The symbolism was significantly enhanced in May when Vice President Walter F. Mondale, despite the strong opposition of Patricia Derian, the State Department's human rights coordinator, yielded to the urging of Holbrooke and Under Secretary David Newsom and traveled to Manila to sign a series of economic aid agreements of a kind that normally would be signed by an ambassador or other lesser official.

The administration's bases priority also provides Marcos with a useful foil for turning aside criticism of his political repression. It was because of the bases that the administration served notice that U.S. strategic interests -- or more accurately, its definition of them -- must take precedence over concern for human rights. The Marcos regime naturally concluded that it didn't have to take American protests over human rights very seriously. Thus, though Marcos' secretary of national defense assured Derian early this year that he would be "the first to order the investigation of any violation of human rights especially if those involved are members of the armed forces," some three months later when I visited the Philippines there was no indication of any investigation of the more than 80 officers cited by Amnesty International as allegedly involved in torture. The Strategic Arguments U.S. OFFICIALS who argue for keeping the bases generally flourish a long list of reasons: their importance to U.S. global defense; their critical role in maintaining an equilibrium among the superpowers in Southeast Asia and for projecting U.S. power into that area; their contribution to the defense of South Korea, Japan and Taiwan; their superior effectiveness for surveillance of Soviet naval shipping in the Indian Ocean; their unique value as a back door for supplying Israel in case of another Middle East war, and their necessity for the defense of the Philippines.

With respect to global defense requirements, the U.S. has placed its major nuclear deterrents elsewhere. We have no ICBMs in the Philippines; our Polaris submarines use facilities in Guam, and we base our B-52s in Guam. It was understood during the Vietnam war that no Philippine government would permit B52s on its territory, so the United States had to build expensive facilities in Thailand and rely on its main base in Guam, from which it cost nearly four times as much to fly as it would have from the Philippines.

The thesis that the bases are essential for maintaining military equilibrium between the great powers in Southeast Asia simply does not stand up. There is nothing approaching equilibrium in the area, the ratio being enormously in favor of the United States. Only the United States has the capacity to maintain a substantial naval force in the area. American base facilities in Guam, Okinawa and Japan are close enough to permit sustained large scale naval deployment there. Moreover, the U.S. has access to facilities of friendly neighboring states, including Australia and Singapore, not available to the Soviet Union. The nearest Soviet base is Vladivostok and it is unlikely that any country in Southeast Asia, Vietnam included, would grant the Soviets a base.

U.S. officials are hard pressed to argue that planes of the 13th Air Force could not more effectively fulfill their primary responsibility of defending South Korea if based in Japan or Okinawa. The same holds for the view that U.S. withdrawal from the Philippines would signal to the Japanese and Koreans that we were abandoning Asia. The Japanese could be expected to welcome the Clark Field squadrons to facilities in Japan. The bases from which the 7th Fleet could most easily defend Japanese and South Korean waters are in Japan, not the Philippines.

Even if there still were vital American interests at stake in Southeast Asia, bases in the Philippines are no longer available for supporting U.S. military activities there. Regardless of whether U.S. public opinion would permit an American president to intervene militarily in Southeast Asia, it is clear that Philippine public opinion would be opposed. In July 1976, Marcos signed an agreement with Hanoi pledging that he would not allow the bases to be used by "any foreign country" for intervention against Vietnam or other countries of the region. The Philippines signed this pact (over strenuous U.S. objections) in part to ensure that Vietnam would not sell arms to the Moslem Filipino insurgents. (Whether or not Hanoi made such a pledge, it has made no arms available.) Access to Middle East

THE ARGUMENT that U.S. base facilities are needed to keep a back door to Israel open is specious. It overlooks recent advances in Air force logistical capacity that permit our huge C5A Galaxies and C141 Starlifters to reach Israel via the Atlantic directly from the United States. Unloaded, these planes can easily make it all the way without refueling and, by availing themselves of midair refueling, they can carry enormous loads -- 20 tons for the C141s.

Should countries of Western Europe again deny overflight permission, in the event of another Middle East war, we could reach Israel by flying over the Straits of Gibraltar because the range of our planes and the state of air tanker transport and mid-air refueling technology have advanced considerably since 1973.

Gen. Poston assured me that if he were given A15s, which are now being made available to both Israel and Saudi Arabia, he could operate toward the Middle East from Guam just as easily as he does with older planes from Clark Field. With ranges of at least 5,000, 6,500 and 7,000 miles respectively, the A15s and the C5A and C141 cargo transports can easily fly from Guam to the intermediate U.S. Indian Ocean base at Diego Garcia. They would only need the single refueling by air tanker that Poston's present shorter range planes require to get there from the Philippines.

Such Guam-based airpower would be as effective in keeping open Indian Ocean sea lanes as planes based in the Philippines. And the assertion that Philippine bases are necessary for Indian Ocean surveillance is outmoded; our Orion planes now make regular use of facilities in Singapore, much closer to the area.

We must not forget that Marcos has already felt the squeeze of an Arab oil embargo imposed as a consequence of his heavyhanded tactics against Moslem insurgents, and would not want a second reprisal. This would be likely if, during a renewal of Middle East fighting, he permitted the bases to be used for supplying Israel. Moreover, such action would antagonize the Philippines' two Moslem neighbors. Indonesia and Malaysia, the latter openly sympathetic to the cause of the Moslem insurgents. The Range of Alternatives

HAS THE United States no choice but to remain in the Philippines, locked into a helpless dependency upon the unpredictable currents of local nationalism and the unpredictable moves of a Philippine dictator? Must American security interests remain hostage to the long-term threat of insurgent activity and the more immediate danger of embroilment in international disputes reflecting Philippine acquisitiveness rather than American defense needs? What are the feasible alternatives to remaining in the Philippines?

Moving the 13th Air Force from the Philippines 1,500 miles eastward to Guam would not pose significant difficulties. That island has well-developed air base facilities, with a longer runway than Clark. A guerilla insurgency is unlikely to be mounted on its 209 square miles of well garrisoned territory, largely people by American citizens. The same would be true of the Northern Mariana archipelago that stretches northward from Guam.

Nor should the potential of the Northern Marianas be overlooked. It was from Tinian, one of the Northern Marianas, that the United States sent a plane to drop an atomic bomb on Nagasaki. Modern aircraft based there, or some 200 miles to the south on Guam, could easily operate in air space above Japan, South Korea and Taiwan. Both Guam and Tinian are closer than Clark to Tokyo.

The main loss in the Air Force's move to Guam and Tinian would be the excellent training facilities in the clark complex. But these could be compensated for by heavier use of existing facilities in the United States or by development of new ones in the Marianas.

For the Navy, withdrawal from Subic would not be the loss that is sometimes alleged. The disadvantages clearly do not weigh so heavily as the threats to its continuing viability posed by unpredictable developments in the Philippines. The 7th Fleet's effectiveness in Southwest Pacific waters would not be greatly impaired if it made greater use of its major base facilities in Japan and Guam. In addition to com munications facilities, Guam has considerable repair and logistical capacity, including a large drydock. If more extensive facilities were needed, these could be built in Guam and the Marianas.

In view of the 7th Fleet's responsibilities for keeping shipping routes open through the Straits of Malacca and its potential role in the Indian Ocean, Singapore is obviously much better positioned than Subic, some 1,500 miles northeast. The Singapore government would welcome greater American use of its modern Serangoon base. Some American officials try to spike arguments in favor of Singapore by asserting that its government makes drydocking facilities available to Soviet ships. The argument is dishonest because the Serangoon base, where Americans are welcome and the Russians are not, is on the other side of Singapore island from the commercial dry docks at Kepple harbor, the only place Russian ships are permitted.

Singapore is also hardly suitable terrain upon which to build up a guerrilla insurgency. Moreover, since the United States has no mutual defense treaty with Singapore, rental of its base facilities would not entail the incompatibility that attends such payment to the Philippines. (Which is not, of course, to say that the U.S. could not defend Singapore if this were to American interests.)

There is also the possibility of using the facilities of Australia at Darwin and North West Cape. These would require additional construction, but one location has well-developed communications and both have runways of at least 10,000 feet.

Moreover, withdrawal of the U.S. military presence from the Philippines need not mean abandonment of repair and logistical facilities at Subic and Clark. As a senior American diplomat said more than a year ago: "With the question of sovereignty and control finally resolved, the government of the Philippines would probably be as delighted as Singapore is to provide us with base facilities when we need them, for a fee." He observed that Manila would also probably accept the presence of small maintenance and repair teams on a permanent basis. Another formula would be to provide repair and logistical facilities at Subic and Clark under contract to American civilian management.

Thus a number of options could meet the needs of the Navy and Air Force. Initially some of them would be more expensive than Clark and Subic. However, they would all carry much less risk of exposing the United States to dangerous local political pressures and military entanglements. The Domestic Factors

WHAT THEN accounts for the administration's cap-in-hand approach to this arrogant Philippine dictator, and why is it unwilling to oppose his demand that the United States pay rent for the bases? One major reason is the reluctance of the U.S. military, especially the Navy, to give up what seems to be a good thing, and the Pentagon's consequent pressure on the administration for retaining the bases. They provide military facilities and physical amenities that are probably unmatched elsewhere outside the United States and unlikely to be duplicated at new bases.

Another is American domestic politics. In a period when the president is under attack for alleged weakness and indecisiveness in matters of defense and foreign policy, the administration believes that withdrawal of the U.S. military presence in the Philippines would strengthen the hands of its critics. This concern has apparently been heightened by the unwillingness of so many senators to relinquish American control over another traditional symbol of American overseas might, the Panama Canal, and the opposition of many of them to phasing out the U.S. military presence in South Korea.

The administration sees the Philippine bases and Mutual Defense Treaty as providing palpable symbols of a determination to maintain a forward position of U.S. power in the western Pacific and concrete evidence that the fiasco of Vietnam does not mean abandonment of a U.S. military capability in Southeast Asia.

A new base agreement with Marcos could dramatize -- as the recent Panama treaty with Torrijos did not -- the administration's resolve to maintain a posture of global military power. Being unaware of the insecure political foundations upon which these Philippine symbols of American strength rest, and of the unpredictable calls which a local insurgency or Marcos' oil claims might make on U.S. power based there, many Americans might find this gesture impressive. Moreover, it will make little difference that the Filipino people are unlikely to regard an agreement with Marcos as having any more legitimacy than the martial law rule under which he negotiated it, and consequently subject to their repudiation when he leaves the political scene. His departure may not be far off, but it is unlikely to come before the next U.S. presidential election.

Whatever the relative weight of these factors, the administration is keeping the United States hostage to unpredictable political developments within the Philippines and to Filipino military requirements that clash with U.S. strategic priorities. And it is doing so while acknowledging that the Manila regime continues to violate basic human rights. This policy reflects calculations of short-term expediency more than it does conscientious and responsible stewardship of fundamental American interests. Map 2, no caption; Map 3, The Washington Post; U.S. Navy photo by Subic Bay, Map by Dave Cook Picture 1, no caption, President Ferdinand E. Marcos Picture 2. no caption, AP