All humanity suffers when a man of democratic vision and political courage is lost. Such a man was Benigno Aquino, who was brutally gunned down as he stepped off the plane returning him to his Philippine homeland after three years of self-imposed exile in the United States. Aquino knew the risks he took by going home. But his compelling desire to restore democracy in the Philippines was stronger than the awareness of danger. It was a sacrifice for others of uncommon magnitude and one which all men of decency will honor.
The facts surrounding the slaying have yet to come to light. President Marcos has deplored the assassination and pledged to catch the killers. But suspicions are strong that the heavily armed Philippine security force at the Manila airport could have prevented the intrusion of a lone assassin and that a regime which had imprisoned Aquino for eight years was directly or indirectly responsible. The onus is on President Marcos to prove the government's innocence.
In the wake of the murder, will the United States reassess what has become a policy of virtually unqualified support for the Marcos government? Will it continue remaining indifferent to a regime that has suppressed human rights and established a new family rule? Unfortunately, Washington has become hostage to the Philippines because of the extensive US air and naval bases there - bases which help protect Western security interests in Asia. But the Reagan administration seems to have gone out of its way to ingratiate the Marcos government, which doubtless feels it has the US by the tail. Two years ago Vice-President Bush told Mr. Marcos, ''We love your adherence to democratic principle and to the democratic processes'' - an outlandish statement that put the US in the worst of lights. And now there seems to be early indication from the administration that President Reagan's planned stopover in the Philippines in November is still on schedule. Could that issue not be deferred pending investigation of the Aquino assassination?
In the context of world opinion, such close US identification with the Marcos government is disturbing. Again we are seeing the case of a country that grows more dictatorial, in which there is a communist insurgency, and in which a government suppression of rights is defended on the grounds of combatting communism. And, if leftist and other opposition continues to grow, the US will again find itself on the side of an authoritarian ruler and seeming to resist the forces of change.
The great need is to encourage a gradual, steady return to democracy in the Philippines. The tradition was implanted, after all, by the United States, which should feel some sense of responsibility for its former territory. Instead of catering to Mr. Marcos, Washington should be putting some distance between itself and Manila. And, while it is up to the Filipino people themselves to demand more democratic rule, the US could help nudge the government in more constructive directions.
Perhaps the whole base question needs reassessment. Some diplomatic experts believe the US could cut back its military and naval presence in the Philippines without endangering security. The US has Guam and other Pacific islands which could be built up militarily. At the least, say these experts, the US facilities at Subic Bay and Clark need not be as lavish as the Pentagon has grown accustomed to. Certainly Congress should scrutinize the new $900 million military and economic aid agreement signed with the Philippines with a view to trimming excesses.
The fundamental question is whether US policy will continue to be based largely on expediency or whether it will begin to embrace a concern about democratic principle. In the long run no nation can be defended by military bases if it tolerates any degree of tyranny, for revolution is the outcome. Aquino understood this. ''Subversion stems from economic, social and political causes and will not be solved by purely military solutions,'' he had planned to say in a message to his fellow countrymen. ''It can be curbed not with ever increasing repression but with a more equitable distribution of wealth, more democracy, and more freedom.''
Aquino's martyrdom will have redeeming value if it rouses the United States and the Philippine people to work for that objective.