Expanded trade, particularly with trading partners that are poorer and more labor-abundant than the United States, is likely to lower the wages of most American workers. While expanded trade is generally win-win at the country level, expanded trade redistributes so much income within countries that its possible to make the majority of residents worse offand this is indeed the likeliest scenario for the United States.
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Some TPP supporters claim the agreement will be all gain, no pain for American workers because U.S. tariffs are already low while trading partners tariffs are higher. These arguments are economically incoherent. In fact, studies that show the TPP will increase overall American national income also show that it will cause substantial reshuffling of domestic production away from labor-intensive import-competing sectors. This will clearly inflict damage on large groups (probably the majority) of American workers.\
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Finally, its worth noting that lots of the export opportunities highlighted by proponents of the TPPincluding in the passage aboveare not necessarily opportunities for U.S. firms to export more, they are instead opportunities to use the TPP to ensure that foreign consumers pay more for U.S. exports. Treaties like the TPP routinely harmonize other nations intellectual property laws to meet U.S. standards, which are very kind to U.S. pharmaceutical and software companies. This essentially means other countries must now spend resources to ensure higher prices are paid by their own consumers to protect the monopoly profits of firms like Pfizer and Microsoft. It is hard indeed to see how this is a win for the wages of the vast majority of American workers.