President Reagan has had a number of opportunities to make a truce with his nation's growing nuclear freeze movement. This could have been done without softening his adamant opposition to the freeze. It could have been done by returning the debate to the merits of the issue rather than the alleged Soviet manipulation of its adherents.
Mr. Reagan missed an opportunity at last week's news conference when he was asked about a congressional committee report minimizing Soviet influence on the basis of FBI and other testimony.
He did make reference to his argument on substance, that he would favor a freeze if the Soviet and American sides were equal in arms. Here is where the debate can be reasonably joined, with cases made for or against the view that there is already sufficient equality or overkill to warrant halting the arms race now.
But President Reagan did not take the chance to get off the ''manipulation'' hook by letting the congressional findings end the matter.
He kept pursuing it and overshadowed the merits of the freeze debate by mistakenly saying that it was Soviet leader Brezhnev who first proposed the nuclear freeze on Feb. 21, 1981.
Followers of the freeze were quick to notice that Mr. Reagan must actually have been referring to Feb. 23, 1981, when Brezhnev gave a party congress speech - and possibly to a magazine article on Soviet influence that said Brezhnev called for ''an immediate cessation of development of any new weapons system'' in that speech. Not so. The speech itself asked for a nuclear moratorium only in Europe.
As for the overall bilateral nuclear freeze as thought of today, Republican Senator Hatfield had called for a version of it in 1979. And so did the 1980 proposal by several US public interest groups, ''Call to Halt the Nuclear Arms Race.''
By belaboring the question of Soviet influence - and with assertions so easily open to challenge - the President invites the response of one of the nuclear freeze campaign leaders: ''Reagan is getting very bad advice from people around him who are making him look like a fool.''
A democratic leader quite properly warns his country that Moscow will seize any wedge to influence opinion and action in its interests. But Mr. Reagan has gone beyond such warning to give Moscow far more credit than it deserves either for peace initiatives or for bending the American people to its will.
This season would be a good one for the President to acknowledge that he does not see millions of Americans as either willing or unwilling dupes of the Kremlin. That he can see thoughtful American citizens as perfectly capable of shaping a nuclear freeze on their own - and worthy of being respected as opponents in vigorous debate rather than belittled as well-meaning people who don't know the score.