There was a time, only a year or so ago, when political leaders, economists, and some business officials, were asking whether the United States should adopt a national industrial policy to spur economic growth. The question is still asked. But now that the economy continues to improve and promises to be a major factor in next year's presidential election, the nature of the debate has changed.
Increasingly asked is not just whether the US should have an industrial policy but, rather, to what extent the various elements of a national industrial policy that are already taking shape should be centralized into a cohesive, intelligent plan for continued and vigorous economic growth.
The policy now evolving is not that of a centralized support for key US industries, as advocated by many Democrats. What is emerging is an ad hoc policy that deals with specific issues. These include steps to boost overseas trade (such as ending the Soviet grain and European pipeline embargoes); imposing import quotas to aid steel and autos; job retraining; urging, as the Reagan administration did this week, that antitrust laws be relaxed to assist funding for research and development; and enacting personal and business tax cuts to stimulate savings.
It is precisely because such an ad hoc policy is emerging from the demands of the economy that Washington officials must think through the long-range implications of the changes now under way. For Congress and the White House to hammer out a hodgepodge of self-conflicting laws would be unwise.
As Harvard professor Robert Reich recently noted, the issue is not whether the US should have an industrial policy, but ''how coherent it will be.''
What minimal steps should an industrial policy include - and not include? First the dubious proposals:
* As recognized by some economists at a recent conference sponsored by the Federal Reserve Bank of Kansas City, the US should avoid aiding specific industries. That means not establishing a multibillion-dollar national development bank. The old Reconstruction Finance Corporation, which some see as a model, was eventually phased out because of allegations of political favoritism. Wall Street investors have a hard enough time picking corporate ''winners.'' There is no reason to think Uncle Sam could do a better job.
* Another questionable element of such a policy would be a national ''superagency'' along the lines of Japan's powerful Ministry of International Trade and Industry.
Now what makes sense:
* Change tax and antitrust laws to direct added dollars into research and development. The dollars could come from the federal government as well as from private industry.
* Federal statistical agencies, such as the Commerce Department, need to provide more timely information about the economy.
* Congress, the White House, and the Federal Reserve should strike a better balance between fiscal and monetary policies to ensure reaching the goals of high employment and price stability. Lurching from inflation fighting to fighting joblessness, and then back again, as has been the case with government in recent years, has hardly helped long-term economic stability.
* The federal government should be doing more to aid financially strapped businesses with job training and retraining programs.
* A new cabinet-level trade department, already proposed in Congress, should be created. An expanding, global, free trade is vital.
Presidential candidates will all want to take a position on a US industrial policy. That should bring the issue before the public in a healthy debate. Such a debate is necessary now that many of the elements of a new industrial policy are already emerging.