The October 1997 Chicago Fed Letter issue, "Economic Gains from Trade Liberalization - NAFTA's impact" by Michael A. Kouparitsas, (available in Adobe Acrobat [.pdf] format only) evaluates the gains from NAFTA.

Recently, the debate over free trade has intensified in light of the failure of President Clinton to obtain fast-track authority from Congress. On September 17, 1997, President Clinton went against the liberals in his own party to request fast-track authority from Congress to negotiate new trade accords. The Senate approved the President's request for fast track on November 5, 1997 but the vote in the House was shelved when it appeared likely that fast-track would be defeated. The opponents of free-trade consist mainly of trade unions who are worried about the loss of jobs to countries with cheap labor, and environmentalists concerned about the effect of free trade on environmental standards. The supporters of free-trade are mainly businesses who see business potential in the larger market that would be created by expanding free trade.