The United States operates a series of radar and missile-defense systems across the Pacific. It includes satellites monitoring the Korean peninsula and fleets of American and Japanese warships equipped with the Aegis system, a powerful computing network that detects and tracks missile launches and aircraft. Those systems are tied to the U.S. Strategic Command’s Global Operations Center, buried deep underground in Nebraska, which monitors events around the world in real time and pumps that information to the Pentagon and the White House.

In the Hawaii incident, there was little danger of the United States firing off a nuclear response. Military officials knew within minutes of receiving the alert that there was no threat to U.S. territory; none of the Pentagon and U.S. spy satellites or the ground and sea-based radars detected any sign of missile launches from North Korea, government officials told me.

But with a president obsessed with cable news and Twitter, the erroneous alert could have easily triggered an angry or provocative tweet, which could have been interpreted by the North Koreans or Russians as an imminent threat. According to pool reports, Trump was briefed on the false alarm while at his private golf course in Florida. Hours later, he tweeted about Hillary Clinton’s “missing” emails and the performance of the stock market. He has yet to comment on the incident despite knowing within minutes that all was safe, even as horrified Hawaiians continued to expect the worst.

“There are fail safes built into the system, but there aren’t enough fail safes,” Kingston Reif, director of threat reduction policy at the Arms Control Association, said. “If the president wants to respond—and there’s very little time to respond—the president and only the president has the sole authority or authorize the use of nuclear weapons,” he added.

President Trump’s apparent attempts to dictate national policy via tweet and his bombastic rhetoric about North Korean leader Kim Jung Un have seemingly raised the odds of a coming conflict. In August, Trump tweeted that “military solutions are now fully in place, locked and loaded, should North Korea act unwisely.” His advisors consistently warn that time is running out to stop the North Korean nuclear and ballistic missile programs

While the United States has a series of sophisticated early warning systems, potential adversaries do not, making initial statements from American officials critical in tense situations. “We have to be concerned about our adversaries early warning systems and their interpretation of these signals and messages,” Kimball said.

Entering this complex array of political signaling, high-tech surveillance, and careless tweeting, is the Pentagon’s new Nuclear Posture Review, the first since 2010. Originally slated for release next month, a draft of the document leaked this past week shows the Trump administration is lowering the bar for what would trigger an American nuclear response. It includes an entire section about non-nuclear strategic attacks that could spur an American nuclear response: cyber warfare, massive blows to critical infrastructure, and certain catastrophic attacks on civilians.