Why Was John von Neumann Guarded on His Deathbed?

David Senra, reading the book's account, says uniformed military personnel watched John von Neumann around the clock on his deathbed because the government feared his mind could be infiltrated and the state secrets in it grabbed during a medically induced state. Claude Shannon called von Neumann the smartest person he ever met.

Shannon met von Neumann among the leading minds of the era. Scientists around them advised the CIA, the Defense Department, and the NSA, and Shannon stayed very reluctant to discuss the classified work even decades later. Von Neumann, one of Shannon's fellow NSA scientific advisors, still had uniformed military personnel with him the whole time he was on his deathbed. The guard was there so nobody could hack his brain. Officials did not treat an impressive mind as immune from infiltration, and a medically induced state looked like the moment to take the state secrets it held.