Recent comments by Presidential Aide Walt W. Rostow indicate that the United States and North Vietnam are secretly and informally exploring the possibilities of a negotiated settlement in South Vietnam. If the current peace feelers are to be any more successful than previous probes, the United State must make it clear that it will end the bombing of the North as a prelude to formal negotiations.

By all accounts, the bombing is serving no military purpose, and North Vietnamese representatives suggested in January that it is the only stumbling block to negotiations. The military inconvenience imposed by the bombing is obviously insufficient to impel the North Vietnamese to the conference table. The overriding effect has been to heighten the Communists' determination to fight on.

The argument that the bombing policy is a necessary psychological booster to the Saigon government and military forces is now outdated. Things have changed since February, 1965, when the bombing began on a regular basis and the Saigon government was on the brink of total collapse. The Viet Cong are no longer in a position to take Saigon, and the Ky government is now far more stable than its predecessors.

But it is the issue of South Vietnam's future governments that may deadlock negotiations between the U.S. and North Vietnam. Both sides must be willing to agree that the National Liberation Front represents a sizable minority of the Southern population, and some provision should be made for its representation in a civilian government. This would involve concessions on both sides, for North Vietnam has insisted that the future of the South should be based wholly on the N.L.F.'s program, and the U.S. has maintained that the N.L.F. is nothing more than a puppet of North Vietnam.

If the U.S. is serious about negotiations, it must realize that stopping the bombing is a precondition to formal conferences, and that allowing N.L.F. participation in the government is a prerequisite for successful settlement. Successful negotiations always entail concessions on the part of both parties.