By 2 to 1, Americans believe the Soviet Union is ahead of the United States in nuclear weapons. By 6 to 1, citizens believe the Soviet Union would secretly violate any nuclear freeze agreement the two nations might make.

Nevertheless, according to the findings of a new Washington Post-ABC News poll, the American public favors an immediate nuclear freeze by both the United States and the Soviet Union by a lopsided 71 to 25 percent, or a ratio of nearly 3 to 1.

U.S. citizens appear to have deep, personal fears of nuclear war, and they believe that both sides have so many weapons now that it doesn't matter which side has more. Support for a freeze is strikingly broad-based: Republicans favor it almost as much as Democrats, men as much as women, conservatives as much as liberals.

In addition, the poll shows, a large majority feels that without public pressure, the U.S. government cannot be trusted to make the right decision on the freeze. Strikingly, this skepticism about the government is shared by both supporters and opponents of the freeze.

The poll also shows that, even while most favor a freeze, Americans also have no appetite for unilateral steps that might put their country at a disadvantage. A substantial majority of the people surveyed said they opposed the idea that the United States promise never to use nuclear weapons until the Soviets use them first.

The Post-ABC poll suggests that the Reagan administration has adopted a very unpopular position by opposing a Soviet-American freeze, but 6 out of 10 proponents of an immediate freeze don't realize that Reagan opposes the idea. However, whereas a month ago the country was evenly divided when asked if President Reagan had done "as much as he should to limit the buildup of nuclear weapons," now, by 48 to 34 percent, people feel Reagan has not done as much as he should.

The poll provides inconclusive evidence about the potential political impact of the freeze movement.

Howard Willens, a wealthy California businessman who is backing a pro-freeze ballot initiative in his home state, said recently that when freeze supporters tell him "there is a great big movement out there in the country , I laugh at them." Instead, Willens said, the seeds of a big movement have been planted, but no one knows how they will grow. "The potential is there to make this a big issue of the '80s, if not the issue," Willens said.

The Post-ABC poll seems to confirm his judgment. The poll shows that only 13 percent of the public is aware of organized pro-freeze groups in their areas, and that 65 percent say they would not join such a group. At the same time, by a majority of 52 to 34 percent, Americans say they tend to approve of pro-freeze groups.

During the last two months, the freeze movement has come out of nowhere to make a strong impression on official Washington. In Congress, 166 members of the House and 24 senators have co-sponsored resolutions calling for an immediate, negotiated and verifiable Soviet-American freeze on nuclear arms. The White House has said it, too, favors a freeze, but not until the United States has built enough new weapons to compensate for what President Reagan has called "a clear margin of Soviet superiority" in current arsenals.

Many of the attitudes recorded in the poll were summarized by a carpenter from Wilmington, Del., a Democrat who voted for independent John Anderson in 1980:

"I'm a grandfather, a father and an uncle. I'd like to see my kids have a chance to live. There's enough destruction, and I think the world leaders should stop the bulls--- and sit down and talk and agree on something. Why should we have to pay for it if they can't get along? They're the ones who started it all, not us."

By 79 to 16 percent, those polled agreed with this statement:

"It doesn't matter if the United States or the Soviet Union is ahead in nuclear weapons because both sides have more than enough to destroy each other no matter who attacks first."

Moreover, Americans appear to have profound personal concerns about the possibility of nuclear war. When asked if concern about nuclear war is near the top of their personal concerns, near the bottom or somewhere in between, 11 percent volunteered that they put nuclear war "right at the top of the list." Thirty-five percent said it was near the top and 26 percent said it was "somewhere in between." Twenty-seven percent put the worry of nuclear war near the bottom of their personal list of concerns, or off the list altogether (11 percent).

In addition, Americans believe by almost 3 to 1 that "the risks of nuclear war starting by accident are growing because both sides keep adding to the number of weapons." Four in 10 said a Soviet-American nuclear war in the next few years is "somewhat" or "very" likely.

Curiously, both opponents and proponents of the freeze agree in large numbers that it might bring negative consequences--that the Soviets might cheat, for example. But opponents are much more likely to believe that a freeze would "make it much easier for the Soviet Union to invade other countries, including those in Europe, without worrying about U.S. retaliation." Opponents agree with that statement by 70 to 24 percent, whereas supporters of a freeze are evenly divided on that possibility.

One-third of the public believes that the United States can win a nuclear war, but half those surveyed said they thought President Reagan believes such a war could be won. The poll suggests that many Americans feel the public needs to send a message to its government. Of those polled, 64 percent agreed that public support for a freeze will force the administration to give higher priority to arms control negotiations.

At the same time, a majority expressed the belief that the superpowers will never be able to agree on a freeze.

"This is a very dangerous and serious matter," said a 57-year-old housewife from Youngstown, Ohio, an independent who voted for Reagan in 1980. "I'm not sure a freeze is at all possible or practical. Neither government can be trusted completely."