Norman David Mayer's one-man siege of the Washington Monument last Wednesday is something most antinuclear activists say they want to forget as quickly as they can, or as one put it, "the less comment (about it) the better."

For while they endorse Mayer's prophecies of doom involving the horrors of the nuclear arms race, they have little sympathy for his methods, which some feel might tar the movement, particularly if it "precipitates a random rash of similar incidents around the country," according to Ground Zero spokesman Ellis Woodward

"His aims were quite good . . . unfortunately in using this kind of violent method you discredit the message and can also discredit those who are trying to get out the same message," said Chaplain Morrison, who is active in a coalition of antinuclear groups called the Montgomery County Citizens For Peace.

But most of those working for a nuclear freeze campaign and greater arms control say they do not expect much adverse fallout on their efforts from last Wednesday's incident which they regard as an isolated one by a disturbed individual.

"I don't think there's any impact, he's a nut . . . there are lots of nuts in this country," said John Isaacs, of the Council for a Liveable World, who added that it was "an obscenity" to use dangerous weapons in a campaign against dangerous weapons.

"There are nuts in the fringes of lots of movements and he was a nut," said Charles Monfort, a full-time lobbyist with the Union of Concerned Scientists. "If he had been a long-standing member of some group, that might have had an effect but he was just an individual who . . . made a misguided attempt to guide arms control policy. What he tried to do was ridiculous."

Most contacted for their opinions heartily rejected any suggestion that the antinuclear campaign's efforts to generate awareness of the horrors of nuclear war have created a climate of fear that may provoke other frightened individuals into outlandish actions such as Mayer's.

Rather, they say it is the Reagan Administration's talk of successfully waging a limited or protracted nuclear war, and its large military buildup which have generated the fears.

A White House spokesman yesterday said: "We would have no direct response to that. We don't make it a habit to respond to these allegations. But the president does not believe that a nuclear freeze would be in the best interests of the country."

"The idea of nuclear weapons is a legitimate fear," said Monfort. "I don't think raising those fears and discussing what to do to reduce them is something we can avoid doing. There are people like Norman Mayer all over the world and you can't let them dictate what you're going to do."