Even if you believe that the Trans-Pacific Partnership will bring benefits to the United States outside of the wealthy, the widespread practice of currency manipulation by the Asian nations included in the TPP is likely to counter those benefits. Robert Scott has a good report about this at the Economic Policy Institute:
Currency manipulation could nullify the benefits of the TPP.
Purchases and holdings of foreign-exchange reserves (broadly defined) would have a direct impact on exchange rates and trade flows in the TPP.
China, as the world’s largest currency manipulator, could affect trade in the TPP in at least two ways. First, as a result of relatively weak rules of origin, the U.S. and other countries would be vulnerable to increased imports from China through the TPP. Second, currency manipulation by China could influence other TPP members to adjust or manipulate the value of their currencies, in order to remain competitive with China, and thereby nullify some or all of the benefits of the TPP to the United States.
Japan is also an important currency manipulator, and this manipulation is the leading cause of the U.S. trade deficit with Japan, which displaced 896,600 U.S. jobs in 2013.
Models that have assumed full employment to evaluate the effects of the TPP and past free-trade agreements should not be used to evaluate the potential demand-shifting effects of currency manipulation on the members of the TPP.
Even if the TPP were a true free-trade agreement it would likely be hard on noncollege-educated American workers, who make up more than two-thirds of the U.S. labor force. Growing trade with low-wage countries is one of the leading causes of the increase in U.S. income inequality. The TPP is likely to reinforce these trends.
The TPP isn’t principally about free trade—it’s about providing increased protection for intellectual property rights for pharmaceutical makers, software vendors, and others, and stronger property rights for foreign investors, which encourages outsourcing, job losses, and a further decline in labor’s share of national income.
Finally, the TPP would likely result in growing trade deficits, trade-related job losses, and downward pressure on the wages of the majority of U.S. workers.
The TPP is simply disastrous for most Americans. But that is unlikely to stop its passage in Congress since even many Democrats buy into neoliberal rhetoric about unrestricted globalization, despite the massive amount of evidence of how free trade agreements have devastated the American working and middle classes without bringing many of the promised benefits to the working classes of globally poor nations like Mexico, Honduras, and Bangladesh.
If you are into destroying the middle class while providing extra protections for powerful corporations and creating non-state courts that allow corporations to escape state power, the TPP is for you. Unfortunately, that includes President Obama.