The GOP leadership has punished its members who have voted against TPP for reasons including not wanting to give even more power to the current president, concern about the flow of LEGAL immigrants into the U.S., and concerns about losing even more of the American manufacturing base.
A reference on this is here http://www.vdare.com/posts/gop-house-leadership-purges-republicans-who-voted-against-obamatrade-and-theyre-all-immigration-patriots
Besides the relationship between immigration and the Trans-Pacific Partnership, this intra-Republican struggle has another connection to the National Question. Check out the NumbersUSA ratings of those Republicans who have been purged:
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