The organization that has pushed for a space-based American defense system to shoot down attacking Soviet nuclear missiles has declared all-out war on leading congressional critics of its ''High Frontier'' proposal.
The group, the American Space Frontier Committee, has targeted four congressmen that it says it is determined to defeat in elections this fall.
''These misguided congressmen and their liberal allies are playing a dangerous game by trying to deprive our citizens of a defense system that could make a nuclear holocaust an impossibility,'' says Monroe Thomas, political director of the American Space Frontier Committee.
The congressmen - George Brown (D) of California, Mel Levine (D) of California, Berkley Bedell (D) of Iowa, and Nicholas Mavroules (D) of Massachusetts - have all been leaders in congressional opposition to space-based weapons systems, including the High Frontier proposal and the Reagan administration's so-called ''Star Wars'' proposal.
The congressmen have expressed concern that such proposals may ultimately lead to a US-Soviet arms race in space. They also question whether such proposals might create a false sense of security.
The American Space Frontier Committee, founded by retired Lt. Gen. Daniel O. Graham, advocates a space-based system of firing heat-seeking nonnuclear projectiles from 432 orbiting battle stations. The projectiles would be designed to shoot down incoming Soviet nuclear missiles while they were still over Soviet airspace.
The committee maintains that such a system could be built within five to six years with existing technology. Committee members say it offers an alternative to the current nuclear defense strategy of mutual assured destruction (MAD).
But a background paper released in April and prepared for the Congressional Office of Technology Assessment as part of a longer-term study of space-based weapons says the High Frontier concept would offer ''meager'' coverage of Soviet intercontinental ballistic missile fields.
The report says the High Frontier proposal is ''a defensive system of extremely limited capability'' to intercept current Soviet missiles in their boost stage, just after launch. It adds that if the Soviets upgraded their booster rockets with quicker burning systems similar to the American MX, the High Frontier system would have ''no capability . . . even with no Soviet effort to overcome the defense.''
Thomas says the Space Frontier group's political action committee has raised
The funds are to be made available on a nonpartisan basis to pro-space-defense candidates in selected congressional races, he says.
''I think it is important for every member of Congress to fight for what he believes is in the best interest of our country and not be dissuaded by such special-interest groups,'' says Congressman Bedell.
''I would be happy that the PAC took every dollar it had and put it into my opponent's campaign,'' adds Congressman Brown. ''It wouldn't worry me one bit.''
''It is very unlikely that the PAC's involvement is going to make one iota of a difference,'' says Bill Andresen of Congressman Levine's office.
''Congressman Mavroules welcomes the challenge,'' says chief district aide Michael Greenstein.
Thomas says that other congressional races are being studied to determine the PAC's chances of success.
According to a press release issued by the political action committee: ''The goal of the American Space Frontier Committee is to send to the Congress men and women who understand that our country must build a defense against possible Soviet missile attack.''
It adds, ''Unfortunately, these congressmen . . . don't understand the need to develop space in a way that could defend our country.''
The Space Frontier Committee maintains that efforts counter to the High Frontier proposal ''make nuclear war more and more likely as each year goes by.''
''I've never seen such a misrepresentation of the truth,'' Brown says.
The congressman, whose southern California constituents include major aerospace contractors, says that to give the impression that space-based weapons systems will provide security to the American people is ''the most flagrant hoax that I've seen.''
''All that I have heard on this issue has indicated that it will be unbelievably expensive and that the possibility of being 100 percent effective is practically zero,'' Bedell says.
The Iowa congressman says that even if only 5 percent of the Soviet's 7,000 strategic nuclear warheads penetrated the space-based defense system, it would still mean 350 nuclear warheads striking the US - ''all bigger than Hiroshima.''
''I think that for any of us to have a sense of false security in a system that still lets us be clobbered with 350 nuclear warheads is a disservice to the country,'' he says.