PRESIDENT Reagan made more than half a turn in the right direction Wednesday night in acknowledging his administration's mistakes in the Iran-contra affair, and in taking direct responsibility for what went wrong. Recovering full confidence with the public and allies must wait on the proven sensibleness of future action, as the President and his advisers themselves admit.
Nothing the President might say now can stop a wider process of evaluation and correction going on in the special prosecutor's office, congressional committees, Central Intelligence Agency - in every government office touched by the Iran-contra scandal.
``I was stubborn in my pursuit of a policy that went astray,'' the President said. This was an extraordinary admission in its first part: More than one top Reagan aide has broken his pick trying to change the President's mind.
The second part was mistaken. For a policy to go astray would imply that it started out aright. Mr. Reagan's arms sale to the Iranians was wrong from the beginning. What Mr. Reagan is still trying to say is that his intention was right, but that people and events messed up. Again, as pointed out by Sen. George Mitchell of Maine in the Democratic response, the problem lay not with people but with policy - and this is the buck that stops in the Oval Office.
Senator Mitchell also said that Americans, Democrat or Republican, want their presidents - this President - to succeed. The Democratic response was, like the President's own talk, constructive. Bygones won't be forgotten until fully aired and corrected. But a big democracy has a big plate of things to get on with. It would be as foolish for the President's opposition - Congress as an institution, not just the Democrats - to spend the next year quibbling over every Iran-contra inconsistency as for the President to think the whole affair will simply sink from sight.
In a democracy there is no one right side. In this democracy, the President cannot claim all right is his. He was elected decisively but still by a minority of Americans, with the greatest energy on his behalf coming from one wing of the political spectrum, the right. That wing is a permanent part of the American electorate. It will not be gone when Mr. Reagan is gone. It will have had two Reagan White House terms to test the market value of its beliefs about strength through arms, populist and conservative family values, the need to downsize the federal government, the Soviet threat, and so forth. It has had an effective champion in Mr. Reagan, but a champion nonetheless with his own Achilles' heel: A stubborn man in the White House can cause a lot of trouble.
Politics tends to exaggeration. It would make mythic figures of people who, like the rest of us, walk the earth without making it tremble.
Nothing has really changed in Americans' common-sense expectations for their presidents. They never expected a Harry Truman, for example, to increase his stature an inch or two. In a democracy, a few individuals rise for a while to run things and then rejoin the rest of the populace.
Strength is in the people. After Mr. Reagan's Wednesday speech, with 17 months to go in his second term, the people may be reassured that this President is seeing things more clearly.