The lady's not for turning -- but the Labour Party is

Last month Britain's Prime Minister Thatcher said, "The lady's not for turning" -- challenging the predictions she would make a U-turn in conservative policies to meet inflation and unemployment. This month Britain's Labour Party swerved to the left with the election of Michael Foot as party leader. The British public appears to be offered choices rather than echoes as the new parliamentary session begins this week.

Just how wide the choices will be will depend in part on the directions taken by a new Labour "shadow cabinet" and on what happens at Labour's special conference in January. It will also depend on how firmly Mrs. Thatcher withstands the growing outcry, and not just from Labourites, against the strong monetarist policies and high interest rates that are bringing business as well as union complaints.

The prime minister is already trailing Mr. Foot in public opinion polls. But she stoutly declares it would be a betrayal to "seek a little more popularity now" by sacrificing hope of future prosperity and stability. And she continues to have strong parliamentary support for her basic strategies. The question is how long the British will accept the reduced standard of living she sees as the price of recovery in investment and employment. For them to do so and to succeed could make Britain a bellwether in coping with change through conservative means as it was in the pioneering of state responsibility for meeting human needs after World War II.

Enter Mr. Foot. He seems like a throw- back to days of increasing union power and nationalization of industry. He has been known for favoring unilateral nuclear disarmament, British withdrawal from Europe, denial of British sites for American cruise missiles. He seems to represent a left-wing Labour minority against the center and right- wing elements that were expected to elect moderate Denis Healey as opposition leader with the support of retiring leader James Callaghan.

Why did a majority of Labour members of Parliament vote for the comparatively radical Mr. Foot? According to some centrist members, he was helped by the conservative victory of Ronald Reagan in the United States. "They wanted to have someone who was as far away from connexions with those generals and new officials as possible," said one of the centrists as quoted in The Times of London.

It was an interesting comment to come at a time that Americans are discussing choices and echoes in their own politics after the Reagan landslide. Some on both the left and right, for different reasons, would like to see Mr. Reagan hew to strict conservative policies -- either to fall on his face or finally prove that conservative policies are the answer to today's challenges. By this reasoning a failure would aid a resurgence of liberalism.

However, more temperate voices call for Mr. Reagan to demonstrate enough flexibility to broaden his base. And, on the liberal side, they call for new "realistic" approaches to achieving liberal goals rather than a return to outworn positions. All sides look to the conservative experiment which began earlier in Britain for instruction both on how to make conservatism work and on what the opposition response to it should be.

Before election Mr. Foot seemed unlikely to offer the kind of fresh realistic thinking on the left that is being sought in the United States. But afterwards he soon began to sound less obdurate and more flexible. Indeed, he was apparently elected partly in expectation that he would be a reconciler of the warring wings of the party. In narrow terms of party mechanics, he was seen as more likely to have his election confirmed under broadened voting procedures expected to be exercised in January.

As to whether Mr. Foot, with an image more of rhetorician than administrator, will demonstrate the qualities of leadership making him a prime ministerial candidate in 1984 -- this will depend on what he and the party do now. Will he assume credible positions and be supported in them? Or will he fail to make himself taken seriously by either friends or foes?

Whatever polls of the moment say, he will have to go some to overshadow Mrs. Thatcher's image, even in the eyes of detractors, as a leader with a sense of direction and a determination to pursue it on behalf of those to whom she promised it.