20 years after losing battle to stop NAFTA, unions are on the warpath again over Pacific deal

Labor unions are trying to stop a major trade pact dead in its tracks, just over two decades since they failed in a bid to stop the North American Free Trade Agreement.

This time the target is the proposed Trans-Pacific Partnership, an agreement to lower or eliminate most trade barriers among the U.S. and 11 other Pacific nations.

President Barack Obama, once a NAFTA critic, is pushing the new Pacific agreement and wants Congress to give him so-called "fast track" authority to move it through Congress untouched, without amendments — just as NAFTA and other major trade pacts were handled.

Sponsors say it would make U.S. companies more competitive worldwide. Unions say U.S. jobs would be lost along the way.