MITT'S MOST IMPORTANT FOREIGN POLICY PLANK:

Global Trade Alert, a monitoring service run by Simon Evenett at the University of St. Gallen, Switzerland, points out that the G-20 countries themselves have been most responsible for the protectionist creep. Many trade measures enacted by G-20 members exploit loopholes in WTO rules.

Unfortunately, President Obama has provided no leadership in trying to keep world markets open for trade. Out of fear of offending labor unions and other domestic constituencies, his administration long delayed submitting free trade agreements with Korea, Colombia and Panama for congressional approval. Instead of seeking to reinvigorate the languishing Doha round of trade negotiations at the WTO, it has been almost completely passive and allowed world-trade policies to drift.

Congress has also done little to help. Senate Republicans and Democrats teamed up late last month to maintain import restrictions for the sugar industry, defeating an amendment from Sen. Jeanne Shaheen (D., N.H.) that would have gradually eliminated them. Keeping domestic sugar prices at twice the world level helps a few sugar-cane and beet farmers at the expense of consumers and taxpayers, while leading to job losses in sugar-using industries, such as candy and confectionary manufacturing.

Meanwhile, Congress and the administration continue to flirt with new "Buy American" provisions, drawing the ire of Canada and other trade partners. Yet economists Laura Baughman and Joseph Francois calculated that if foreign retaliation led U.S. companies to lose just 1% of the potential sales opportunities created by foreign stimulus programs, U.S. exporters would lose over 200,000 jobs. This would far exceed the 43,000 jobs supposedly created by the "Buy American" preferences included in the 2009 stimulus bill.

Any serious march backward toward protectionism would constitute a major failure of economic policy.

Follow @brothersjudd