Years ago, a labor leader explained to us why his union opposed free-trade pacts. “You have to understand,” he said, “we only represent workers who have jobs now. We don’t represent workers who might get jobs in the future.”

Those views are understandable but destructive. In today’s dynamic global economy, change has to be embraced, not rejected. That’s why Democratic leaders cannot afford to listen to the labor movement as the country approaches a major debate over trade policy.

That debate was triggered by a “historic bipartisan breakthrough,” in the words of U.S. Trade Representative Susan Schwab. As announced last week by the Bush administration and key Democrats, the agreement says that future trade pacts have to protect workers’ rights and promote the environment.

Organized labor has long demanded this development, but they refused to take yes for an answer. Clearly, they don’t want any new trade pacts of any kind. James P. Hoffa, head of the Teamsters, ranted that the deal “sells out American workers (and) does nothing to protect American jobs or help create more jobs at home.”

That’s exactly the kind of reactionary, head-in-the-sand view expressed by the labor leader we quoted above. And that’s exactly why Democratic leaders have to stand up to their old friends in the labor movement and tell them the truth: trade is vital to American prosperity and security, and you don’t get a veto here.