Chinese and U.S. nuclear experts spent a decade plotting out the Ghana operation, sharing expertise and working at each other’s labs. “No question, we were able to collaborate very, very well on the MNSR conversion,” says Ernest Moniz, CEO of the Nuclear Threat Initiative (NTI), a think tank in Washington, D.C., and former secretary of the U.S. Department of Energy (DOE). The process strengthened a bond that is quietly developing between nuclear scientists in the United States and China. “It’s very important for building trust,” says Hui Zhang, a nuclear policy analyst at the Belfer Center for Science and International Affairs at Harvard University.