I started a conversation with Jacob Levy about congressional approval of trade agreements last week and then got too busy to continue it. Levy argued that trade agreements are most reasonably seen as treaties and thus require 2/3ds approval from the Senate to conform to constitutional requirements. The current practice is to pass the agreements with a majority vote of the House and the Senate. Also, Congress, by passing “fast track” or “trade promotion authority” legislation, commits itself to considering the trade agreements without amendments (on the theory that other countries will not conclude agreements if their terms are up for grabs on the floor of the House).
Levy worries that the practical consequence of taking his constitutional concern seriously would be an end to trade liberalization. But perhaps his constitutional argument is a reason for going about that liberalization in a different way. Congress can (and should) repeal tariffs and quotas unilaterally. If trade agreements were replaced by what Brink Lindsey has called “co-ordinated unilateralism,” the constitutional objection would fall away. And free traders would be able to make economically sound arguments for their objectives.