Before it adjourns for a long Easter recess, Congress hopes to wrap up work on a new foreign trade bill.

Despite considerable compromises between widely varying House and Senate versions, the measure still contains so many protectionist provisions that it's hard to see how the lawmakers can produce an acceptable bill in the little time that's left.Consequently, if Congress won't take the additional time and effort needed to formulate a bill more in keeping with the principles of free trade, President Reagan should feel no qualms about making good on his threat to veto the new measure.

Mr. Reagan is particularly concerned about provisions that would mandate U.S. retaliation against certain foreign trade practices, require 60-day notification for U.S. plant closings and layoffs, and require disclosure of financial data by foreign investors.

What's wrong with such provisions? Among other things, they would deprive the White House of much of the flexibility it now has in deciding where and when to react to seemingly unfair competition, impose higher costs on some U.S. firms, and deter foreign investment in the U.S. even though it can help stimulate the American economy.

If the president's resolve to veto an unacceptable trade bill needed any stiffening, that certainly should have been accomplished by the fate of Richard Gephardt, who this week bowed out of the race for the Democratic presidential nomination.

For two years now, Gephardt -- who authored some key provisions of the new trade bill -- has been trying to tell Americans to get tough with Japan, West Germany, and other U.S. trade rivals.

But Gephardt's pitch fell on deaf ears even in Michigan and the South, despite the fact that these sections of the country have been hit particularly hard by foreign cars and textile imports respectively.

When Massachusetts Gov. Michael Dukakis wavered on his own free trade stance and started mouthing Gephardt's words on trade, Dukakis fell flat in Michigan, too.

Judging from this experience, Americans seem to have learned that when the U.S. starts limiting imports it invites retaliation from its foreign trading partners, saps the incentive of U.S. manufacturers to compete by offering better products at lower prices, and penalizes American consumers.

The message should be clear: Protectionism has long been bad economics. Now it seems to be bad politics, too.