To overcome their "brain drain," some developing countries employ the "Diaspora Option," encouraging their overseas nationals to use the knowledge they gained abroad to help their motherland. Since the mid-1990s, China's party/state has vigorously used an extensive array of programs and incentives to persuade ethnic Chinese living in America to transfer their technological knowhow back home. Many Chinese working abroad facilitated this flow, some to strengthen their former homeland, others from self-interest. In 2018, the Trump Administration declared war on these efforts. Employing a McCarthy-like campaign called the "China Initiative," the government investigated Chinese scientists across the U.S. Many individuals were arrested, only to have their cases dropped. Still, hundreds had their research disrupted or lost their jobs. This book documents China's 'no-holds-barred' effort to access U.S. technology and America's vigorous counterattack and its efforts to disrupt the transfer of U.S. technology to China. It highlights how the war has undermined Sino-American scientific collaboration and triggered the outflow of some top Chinese talent from America and back to China.