In the 1980s, Fu Xiangdong was a young Chinese virology student who came to the United States to study biochemistry. More than three decades later, he had a prestigious professorship in California and was conducting promising research on Parkinson's disease. But now Fu is doing his research at a Chinese university. His American career was derailed as U.S.-China relations unraveled, putting his collaborations with a Chinese university under scrutiny. He ended up resigning. Beginning in 1978, U.S.-China academic cooperation expanded for decades, largely insulated from the fluctuations in relations between the two countries. Today, it's in decline, with Washington viewing Beijing as a strategic rival and there are growing fears about Chinese spying.