TerraPower, a nuclear-energy company founded by Bill Gates, is unlikely to follow through on building a demonstration reactor in China, due largely to the Trump administration’s crackdown on the country.

Why it matters: This is a blow to America's attempts to commercialize advanced, smaller scale nuclear technology and, separately, further evidence of soured relations between the U.S. and China under President Trump.

Driving the news: In a year-end blog post covering various topics published Saturday night, Gates said of TerraPower: “We had hoped to build a pilot project in China, but recent policy changes here in the U.S. have made that unlikely.”

Details: The Trump administration, led by the Energy Department, announced in October that it was implementing measures to “prevent China’s illegal diversion of U.S. civil nuclear technology for military or other unauthorized purposes.”

Those measures have made it nearly impossible for TerraPower’s project to go forward, according to multiple people familiar with the development.

TerraPower had pursued plans to build a pilot reactor in China because that country has two things America doesn’t — growing electricity demand and a long-term strategic energy plan — a top TerraPower executive told me last year

Morning Consult an analyst

For the record: “The Department of Energy continues to support the development of advanced nuclear reactors in the United States by Terrapower and others. This cutting edge technology has the ability to offer Americans a clean and resilient resource for electricity and other purposes," said Energy Department spokeswoman Shaylyn Hynes in an emailed statement.

"DOE also sees opportunities for global exports of this technology to nations who seek to develop their own civilian nuclear power programs for peaceful purposes.”

The big picture: Gates has long been bullish on combating climate change with advanced nuclear energy because the technology is carbon-free and smaller and deemed safer than existing nuclear plants. He founded TerraPower a decade ago, and next year he plans to speak out more about how America needs to “regain its leading role in nuclear power research,” he said in his blog post.

“Unfortunately, America is no longer the global leader on nuclear energy that it was 50 years ago. To regain this position, it will need to commit new funding, update regulations, and show investors that it’s serious.”

— Bill Gates

What’s next: “We may be able to build it [the reactor] in the United States if the funding and regulatory changes that I mentioned earlier happen,” Gates said in his post, although he didn’t specify which funding or regulations.

Meanwhile, the Energy Department just announced

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