In an era of polarization, trade is the rare issue on which leaders of both parties agree.
Which is why odds are high that a Republican Congress will give President Barack Obama the negotiating authority he seeks to conclude an Asian trade deal. Senate Finance Committee approval of Trade Promotion Authority legislation Wednesday night is only the first step—but its bipartisan 20-6 vote made it a strong one.
Republicans believe in trade expansion as a matter of free-market philosophy. In recent years, their tea party faction has slightly tempered that support with its suspicion of Big Business and Big Government alike. But on this issue its influence is no match for that of corporate interests who donate heavily to GOP campaigns.
Democrats are more skeptical of unfettered markets. Their labor union and environmental wings can back their hostility to trade expansion deals with both money and votes. That's why both Trade Promotion Authority and the Trans-Pacific Partnership are far more controversial within the Democratic Party.
Yet at the highest levels, Democrats, too, have come to view trade expansion as in America's economic and national security interests alike in a world of global interdependence. President Bill Clinton, relying largely on Republicans, pushed through the North American Free Trade Agreement with Canada and Mexico and permission for China to enter the World Trade Organization.