Barry Goldwater tends to be at his best when blowing off steam. From his celebrated 1964 dismissal of Eastern liberals--that "it would be a good thing to saw off the Eastern Seaboard and let it float out into the Atlantic"--to his 1976 blast at a fellow Republican then in Peking--"As far as I'm concerned, Nixon can go to China and stay there"--Goldwater's talent enfor steam-blowing is one to which he has been passionately devoted.

It has helped that he has been devoted to little else. In 24 years in the Senate, he has not stood out as the author of any major social legislation. Nationally, large groups of the disenfranchised do not seek his help in their struggles against injustice. No political clich,e --peace through strength, the Republic is in danger--has been too meaningless for him to spout.

But it can't be denied that Goldwater is the Senate's champion rager. He was at it again the other day, hollering in full-lung fury at Jerry Falwell and other moralizers of the New Right: "I'm frankly sick and tired of the political preachers across the country telling me as a citizen that if I want to be a moral person, I must believe in A, B, C and D. Just who do they think they are? And from where do they presume to claim the right to dictate their moral beliefs to me?"

Like the tough Air Force general that he is -- retired and on reserve, we should be grateful-- Goldwater said he was "warning them today: I will fight them every step of the way if they try to dictate their moral convictions to all Americans in the name of 'conservatism.'"

Behind the bluster, Goldwater has little reason to scorn Falwell. They are fellow travelers. Their thinking is interchangeable.

Here is Goldwater in his memoir, "With No Apologies": "however much we've changed the shape of man's physical environment, man himself is still sinful, vain, greedy, ambitious, lustful. . . ."

Falwell, in "Listen America!" writes that "man by nature is not good. . . . People are living and dying for money. We see drug addiction and alcoholism and people worshiping the idol of and the god of sex."

For Goldwater, "the Russians are determined to conquer the world. They will employ force, murder, lies. . . ." For Falwell, the "Communists have dedicated themselves to world conquest." And: "The Soviets are liars and cheaters."

Goldwater laments the "alarming decline in American military power," while Falwell declares that the "United States has been severely declining militarily."

What's the difference? Johnny One-Note, conservatism's most sought-after author, has ghosted the texts for both.

Goldwater would have us believe that it's not the values of Falwell and his ilk he is damning-- "I happen to share many of them," he says--but their tactics. The single-issue reverends upset the senator because they have an "unrelenting obsession with a particular goal."

Who is Goldwater to be suddenly against obsessions, considering his and the right wing's obsessive and wildly exaggerated fears of Russia? It is these fears--expressed in one decade that the Russians are coming by missiles from Cuba, the next that they are coming in on the West Coast after knocking over Far East nations like dominoes and today by warheads that only the MX can stop--that have created an arsenal of weapons unprecedented in history.

In his resentment of single-issue groups like the Moral Majority, Goldwater conveniently forgets that the most effective and enduring single-issue group in America is the military lobby. With the Reagan military budget soaring, is any other single-issue group more successful? Out to "re-arm America," what other group has a greater "unrelenting obsession with a particular goal?"

Against the single-issue zealots who whip Congress and the country into greater and greater frenzies of military spending, the Falwells are benign dreamers. Goldwater has no ideological argument with them. Nor has he any reason to hold his nose about their tactics. They are pure right wing, both ways. Mr. Conservative taught them well.