In June 1983, Ronald Reagan settled in for a movie night, choosing a newly released film that had been sent to the White House for an early screening: WarGames. The story struck him immediately. In the film, a computer-savvy teenager accidentally hacks into a U.S. defense supercomputer. Believing he’s simply playing a game, he triggers what appears to be a full-scale nuclear war simulation. The problem is that NORAD interprets the simulation as real, setting off a frantic race against time to prevent an actual nuclear exchange.

The plot captivated Reagan so deeply that, a few days later, during a White House meeting on nuclear security, which his presidential diaries date to June 10, he brought up the movie in detail with his advisors. It wasn’t unusual for him to start a policy discussion with a film he had recently watched, but this time he had a very specific concern: could ordinary citizens, now increasingly equipped with personal computers and phone-line connections, actually break into classified military systems?

The question had never been raised in previous security briefings. General John Vessey, newly appointed Chairman of the Joint Chiefs of Staff, promised to investigate thoroughly. About a week later, a detailed report landed on the president’s desk, and the findings were alarming. Security on U.S. defense networks was extremely weak; passwords were simplistic; and the possibility of unauthorized intrusion had never been seriously examined. In fact, the report suggested it was entirely plausible that an outsider might soon attempt to infiltrate the system.

The bureaucratic and legislative machinery reacted quickly. The following year, Reagan signed National Security Decision Directive 145 (NSDD-145), placing military computer systems, government networks, and even some civilian systems linked to the federal government under the protective authority of the NSA. The agency’s newfound power grew so vast that Congress eventually stepped in, passing the Computer Security Act of 1987, which imposed limits on the NSA’s authority over civilian networks.

WarGames, though visibly dated today, is still regarded as a cult classic. Beyond its entertainment value, it offered audiences a glimpse into the early, improvised world of hacking, and unintentionally helped spark a major shift in how the United States approached computer and information security.