(FORTUNE Magazine) – By standards commonly invoked in the past, American labor relations would seem ; to be remarkably serene. Strike activity is at a post-World War II low: In the latest 12-month period, only about 1/10,000 of all worker-hours were lost because of stoppages. In past decades, the figure would typically have been ten times higher. The number of unfair-labor-practice charges filed annually with the National Labor Relations Board is running around 35,000, well below the levels of the 1960s and 1970s, and the proportion of NLRB cases settled amicably is a highly satisfactory 90%. So obviously U.S. labor relations are a noncrisis situation that will trigger absolutely no ''reforms,'' right? One is, of course, jesting. Electorally beholden to Big Labor, the Clintonites are committed to Big Reform. Its obvious point is to see whether the endless decline of American unionism, which now represents only about one- sixth of all workers -- and only one-ninth in the private sector -- can somehow be reversed. To be sure, that is not the stated objection. Preferred smarmy formulation of Labor Secretary Robert Reich: The team wishes merely to ''close the book on an era of hostility and distrust.'' Noble, eh? For some of the Administration's proposals, you must apprehensively await hearings of the new Commission for the Future of Worker-Management Relations, to be chaired by John T. Dunlop, a Harvard professor emeritus who in his day has chaired thousands of meetings in Washington and come out of every one of them believing a large union sector is good for the people. But the main proposal is embodied in the Workplace Fairness Act (WFA), which would bar employers from hiring permanent replacements for those of their workers who hit the bricks. It seems that this proposal will not require any commission hearings. Reich told reporters several weeks ago that it ''doesn't need to be re-researched,'' explaining crisply, ''On this issue, the President has already made up his mind.'' The WFA has some built-in logical and public relations problems. American employers have always had the right to replace workers who struck, although the right was not formally elaborated until a 1938 Supreme Court decision, NLRB v. Mackay Radio. Still, the Mackay doctrine has now been on the books for 55 years, during most of which union power was far greater than it is today. There is no public clamor for changing the law. Indeed, Americans appear to believe that it is generally a good idea for workers contemplating a strike to worry that it could cost them their jobs. A Yankelovich Clancy Shulman poll for Time and CNN last year showed only 29% favoring repeal of Mackay, vs. 60% for no change in the law. With labor relations looking more tranquil than ever, how do you sell the need for ''reform''? Carrying the ball on this issue, Reich has labored to promote the following story line: For most of its long history, Mackay was in fact no problem, since employers hardly ever invoked their theoretical right to replace brick hitters. But then, in the years of Reaganite reaction -- and especially after Ron showed employers how to do it by firing all those Patco air-traffic controllers -- business reversed course. As Reich put it in his March 30 testimony to a House labor subcommittee, Reagan's action ''sent a loud signal to the business community that the hiring of permanent replacement workers was an acceptable way of doing business.'' Real bargaining is now impossible, said Reich, since workers feel ''a gun ((is)) pointed at the union's head.'' It all sounds facially plausible until you listen to Daniel V. Yager, a Washington-based lawyer frequently found on management's side of the table. In his own subcommittee testimony, delivered on May 5, Yager documented certain factual difficulties in Reich's story line. For openers, he pointed to plenty of striker-replacement behavior before Patco. He cited NLRB data showing no increase in such behavior after Patco. Finally, he demonstrated that very few strikers ended up being replaced during the decade. Surveys by the General Accounting Office showed that only 4% of all strikers were replaced in 1985. The figure for 1989 was 3%. The notion of a post-Patco transformation of employer behavior is simply not discernible in the data, nor is the proposition that companies are holding howitzers to union heads. The scorecard here says that Yager has won the argument, but Reich may well win the war. The ban on striker replacements is a cinch to pass the House of Representatives and has fair prospects in the Senate. Clinton has vowed to sign it in a flash. This could be the promise he keeps.