In April 2018 a US Congressional Subcommittee spent a full afternoon discussing whether Chinese students at US universities were bona fide scholars or were spying for the Beijing government. The fear that the openness of US universities would be abused by communist rivals was manifest in the Reagan years; it has reached new heights with the current administration. This talk will place these fears in historical perspective, emphasizing the singular importance the United States places on controlling access to advanced scientific and technological knowledge. John Krige will argue that China’s appetite for advanced knowledge is seen as posing an existential threat to American national and economic security. The countermeasures taken by the Trump administration, specifically targeted at Chinese nationals, cannot simply be brushed aside as temporary moves by a president who thrives on confrontation. They will continue and be reinforced over the years ahead, demanding major concessions to the principle of academic freedom by American universities in the name of national security.