The citizens of Weston, Vt., population 650, tried to show their leaders the way by voting a cutoff of military aid to El Salvador at their March 1 town meeting.

Local Republicans were mortified at this new repudiation of President Reagan's foreign policy. Last year Weston voted unanimously for the nuclear freeze.

El Salvador's ambassador, Ernesto Rivas-Gallont, pleaded for and was granted an emergency hearing in a special town meeting last Friday night.

He was heeded most courteously and given a standing ovation, but the vote stood.

It is perhaps too much to hope that Congress will act so bravely in dealing with Reagan's request for $110 million for military aid, although it knows that there is no popular support for more of the same in El Salvador.

Reagan's rhetoric has grown increasingly apocalyptic and intimidating as the government situation deteriorates.

Our national security is at stake, Reagan said.

The Rev. Jerry Falwell, leader of the Moral Majority, is of like mind. He told his flock in Lynchburg that "If we do not fight them in El Salvador, we will have to fight them in El Paso."

If Reagan really believes that we are imperiled by those ragged forces fighting in the hills, he should be asking 10 times more in money and arms for the tottering regime. He should be mobilizing the 82nd Airborne. He should revive the draft.

Instead, he bids us be thankful that he is not sending American troops.

That, to him, is proof positive that there is no comparison between El Salvador and Vietnam.

While insisting there are no parallels, administration spokesmen continually invite them, by talking about "dominos." Never mind that one of the countries said to be slated for domino-doom, Mexico, is in the forefront of Salvadoran neighbors calling for negotiations.

You would think that if the example of Weston and 12 other Vermont towns whose citizens advised the central government to be done with it in El Salvador could not stiffen Congress, a study of the statistics might.

Thirty thousand non-combatants have been killed in El Salvador since the onset of the civil war, which Reagan sees as a Communist aggression fueled by Moscow and Havana.

Of these murders, none has been solved. Not a single member of the security forces or the "death squads" has ever been convicted.

Most recently, in the case of the four American churchwomen who were killed in December, 1980, an appeals court ruled that there is "insufficient evidence" to bring to trial five Salvadoran national guardsmen who were indicted more than a year ago.

There always is, and as far as can be determined, always will be, "insufficient evidence" for justice to be done. Salvadoran law is a rickety structure, and, with the examples abounding of the danger of provoking the government, no judge is willing to pass judgment on a member of the security forces.

This has not prevented the Reagan administration from continuing to certify El Salvador's "progress" in human rights. Fewer murders are cited, without regard to the fact that there simply are fewer people to be murdered each year.

But Congress has a problem that small towns in Vermont do not have. It has a fear of being asked, "Who lost El Salvador?" Those who do not believe that the Soviets are coming, who blanch at subsidizing slaughter, are nervous about political reprisal.

Reagan obviously will fight to the last peasant. If Congress balks on aid, he will accuse them of expediting a Marxist takeover--which might be averted if he would agree to negotiations now.

Rep. Michael D. Barnes (D-Md.), chairman of the Hemispheric Affairs subcommittee, told the Council on Foreign Relations Sunday night that if the president wants $60 million he should come to Congress and ask for it in the regular fashion, instead of the back-door approach--reminiscent of Vietnam--a "reprogramming" from other funds. Barnes' subcommitee must act on the "supplemental" request for the other $50 million.

One member of the House Appropriations subcommittee that must pass on the reprogramming said he will vote "no" unless he gets definite assurances that a political solution will be sought. Rep. Matthew F. McHugh (D-N.Y.) said, "Without a clear promise of negotiations and some specific steps as to how they could be arranged, I will vote against any military aid."

McHugh pointed out that further military aid simply strengthens the extremists in the military and muzzles moderates in the government who might be able to come to terms with the moderates in the political leadership of the guerrillas.

But most of the common sense about El Salvador seems to lie beyond the Beltway.