In reading Mary O'Grady's fine column on the presidential debate exchange over the U.S.-Columbia Free Trade Agreement, this passage caught my attention:

But when Mr. McCain pointed out that opposing the U.S.-Colombia Free Trade Agreement doesn't make sense -- because the U.S. is already open to imports from Colombia and because the agreement will open new markets for U.S. exporters during rough economic times -- Mr. Obama was caught flat-footed.

If Ms. O'Grady is correct that the deal is essentially a reduction in Columbian trade barriers, then why doesn't Columbia simply drop its barriers and avoid dealing with the do-no-good U.S. Congress? I must be missing something here.