So billions of dollars in subsidies from U.S. taxpayers, that helped Tesla (Musk) develop and refine a technology that may or may not finally become profitable, is going to be essentially handed over to a partner in a country that has a deserved reputation of not respecting international patents and trade law. 

To think that there was actually talk, for a while (pre- Paris Climate Agreement cancellation), of how Trump and Musk might actually get along because Tesla and Solar City were USA made and developed, fitting right in with Trump's "buy American" ideology.