From Marginal Revolution:
In a word, Vietnam. Vietnam has about ninety million people and a relatively low per capita income, below by 2k by some measures. It liberalized tariffs a good deal upon WTO accession, but since then has done some backsliding. It has large numbers of state-owned enterprises, and its policies toward such enterprises could use more transparency and predictability, as indeed TPP would bring. Most generally, Vietnam is not today a free country. Bringing Vietnam into TPP would further ensure their attachment to a broadly liberal global trading order. TPP also would bring free(r) labor unions to Vietnam.
Tuong Lai writes (see the first link above):
But Vietnam cannot play its significant geopolitical role until it fully develops economically and further liberalizes politically. And adopting the T.P.P.’s requirements — free trade unions, reduced state participation in the economy, greater transparency — will help Vietnam along that route.
Many potential TPP signers still have significant tariffs against Vietnamese textiles? Here is Jack Sheehan:
Vietnam is set to gain the most from the TPP due to the potential for a greater share of the apparel and footwear market, particularly in the US and Japan.
In 2012, Vietnam exported almost $7bn (£4.2bn) worth of apparel to the US, which accounted for 34% of US apparel imports. Vietnam also exported $2.4bn worth of footwear.
The TPP will allow Vietnam to export apparel to the US at a 0% tariff rate, which will make Vietnamese exports even more competitive.
Here is an assessment from the Peterson Institute that Vietnam will be the biggest gainer from TPP. Do you get that, progressives? Poorest country = biggest gainer. Isn’t that what we are looking for? And if you are a deontologist, Vietnam is a country we have been especially unjust to in the past.