Paula Stern, chairwoman of the International Trade Commission, likens the agency's work these days to the daily cops-and-robbers routine on "Hill Street Blues," the popular TV show.

"The ITC is the cop on the import beat," she said in a recent speech. "The alarm bells rung by American producers who claim that they are being victimized by competitors dumping goods, subsidizing sales, pirating discoveries or violating trademarks make my office seem something like the Hill Street station during a gang war.

"I can understand the instinct to 'go out and do it to them before they do it' to us. But I cannot justify our following that primal urge in international trade."

Stern, a Democrat with seven years on the commission, became chairwoman in 1984, not because the Reagan administration is entranced with her but because it was her turn under a rotation system. Lately, she has been underscoring the point that ITC decisions in unfair-trade-practices cases will have only a small impact on the vexing problem of the $150 billion annual American trade deficit.

In a few days, the commission will decide one of its most important cases in recent years. The American semiconductor industry, this time supported by the U.S. government, charges that Japanese companies are engaging in unfair trade competition.

Naturally, all ITC commissioners scrupulously avoid discussing individual cases still before them. But a visit to Stern indicates that the outspoken chairwoman -- however she votes in the semiconductor case -- believes that laws offering U.S. companies relief from the strains of import competition merely nibble at a minor facet of the problem.

In an era of growing protectionist sentiment in the business, labor and government communities, it takes real guts to lay that truth on the line: imports often are not the source of an American company's problems. And even where they are, most of the supposed remedies don't work. Today, the only effective tool available to the ITC, says Stern, is quotas. And quotas, as we have seen in the auto and steel industries, don't necessarily make a domestic industry competitive.

"Too many people say we'd get back the jobs we've lost if we'd just eliminate the imports," says Stern with a show of anger. "That's just not so, and it's a deception to suggest it."

She unhesitatingly throws back at Lee Iacocca one of the Chrysler Corp. chairman's favorite lines. It is the one suggesting that if only American industry had "a level playing field" it could handle the competition with Japan or anyone else.

This conveniently suggests that the auto industry's multiple failures are not its fault, but someone else's. And it provides a cover for Chrysler's partnership deals with Asian producers that effectively ship American jobs abroad.

Stern has little patience with such oversimplification. "To explain away (the 1985 trade deficit), we have to look beyond the ways in which foreigners close their markets and abuse the open hospitality of ours," she says. "Our chief concern need not be the level of the playing field. We must concentrate instead on building the strength of the American team."

She argues for a move away from the protectionists' fixation that imports are the problem, and that quotas, tariffs and other forms of trade "relief" are the solution. Instead, she would make industry's and labor's willingness to become more competitive the test for any government assistance.

To be sure, this is not a new idea. But Stern, after participating in more than 1,000 industry complaints since 1978, is in a unique position to assert that "the approach that focuses narrowly on imports often overlooks more basic causes of competitive decline." In these cases -- where import relief isn't justified -- the government "should not walk away" from attempting to solve the underlying problem, but should demand something in return for its help. "If we'd extract something that we know is good for them, we'd all be better off."

That calls for stronger leadership by the president, who needs to become "strategist-in-chief" to overcome the trade deficit. This theme has also been sounded by Democrats on the Hill, and the similarity is not coincidental. "I'd like to think that I can influence the debate in any way I can," she smiles.

Stern makes a good case. But the logic of her thinking could get lost in an election year as Congress, as is its wont, gets caught up in the monthly trade statistics, likely to look bad, even with the dollar declining. Perhaps a harbinger of what lies ahead was the outburst in Tokyo this week by Sen. John Danforth (R-Mo.), who said in a John Connally- like phrase that Japan must "learn that there's more to leadership than flooding the world with Walkmen and VCRs." More Japan-bashing isn't the answer to job creation.