Brian Snyder / Reuters

After Sunday’s mass shooting at a gay nightclub in Orlando, Florida, Donald Trump was quick to respond. He delivered a speech on Monday intended to address what he called “the growing threat of terrorism inside of our borders.” The Republican Party’s presumptive presidential nominee reminded the world of his call for a temporary ban on Muslims entering the country. He promised to “protect and defend all Americans who live inside our borders.”

Counterterrorism experts warn that politicians should not exaggerate the threat of terrorism or create unrealistic expectations about what they can do to keep the country safe. Yet in his speech, Trump dramatized the danger facing the United States and made promises that would be difficult for any president to keep—a reaction that could make it more difficult for the U.S. to respond effectively to the threat of terror.

Exaggerating the risk of terrorism can lead to public demand for a disproportionate response to an attack. During his speech, Trump suggested terrorism poses an existential threat to the U.S., even though terrorist attacks in the U.S. remain relatively rare. Trump called the Orlando shooting “a strike at the heart and soul of who we are as a nation,” adding, “if we don’t get tough, and we don’t get smart—and fast—we’re not going to have a country anymore—there will be nothing left.”

At best, exaggerating the threat of terrorism “means we lose perspective,” said John Horgan, a professor who studies the psychology of terrorism at Georgia State University. “We need to be able to talk about these threats in an informed way. And if we don’t, we will end up with counterterrorism policy grounded in emotions instead of evidence.” As Micah Zenko, a senior fellow at the Council on Foreign Relations, wrote a few years ago, Americans are about as likely to die in a terrorist attack as they are to be fatally crushed by their own furniture. “This is not to diminish the real—albeit shrinking—threat of terrorism,” Zenko concluded. “For Americans, however, it should emphasize that an irrational fear of terrorism is both unwarranted and a poor basis for public-policy decisions.”

If political leaders look for scapegoats or inaccurately assign blame for terrorist attacks, they can make it more difficult for the government to evaluate and respond to threats. As Trump described his plan for immigration restrictions on Monday, he suggested immigrants pose a grave threat to the U.S., in at least one instance without offering clear evidence. He promised to “suspend immigration from areas of the world when there is a proven history of terrorism against the United States, Europe, or our allies, until we understand how to end these threats.” He added that “we cannot continue to allow thousands upon thousands of people to pour into our country, many of whom have the same thought process as this savage killer.” (A Trump spokesperson did not respond to a question about where this number came from.)

“Trump already has a tendency to overstate, exaggerate, and sometimes say things that are simply wrong,” said Martha Crenshaw, a terrorism expert at the Center for International Security and Cooperation at Stanford. “In this case, the danger is that you stereotype a very large group of people as a danger to the security of the American homeland when it’s simply not true.”

Crenshaw’s research indicates there have been roughly 220 jihadist perpetrators or would-be perpetrators of violent terrorism against the U.S. since 1993. Most of the plots were unsuccessful. “When you leap into this and assume you know exactly why somebody did something and then blame a certain set of beliefs or ideas such as a religion or associate a person’s actions with an entire community of people, that narrative can take on a life of its own,” Crenshaw said. “It can be very difficult to correct these initial assumptions and assertions, even when they are not correct.”

Any claim that politicians can completely safeguard Americans from future terrorist attacks is unrealistic. In his speech, Trump made sweeping pledges to keep the country safe. He vowed to “protect and defend all Americans who live inside our borders” and “ensure every parent can raise their children in peace and safety,” promising outcomes no politician can guarantee. 

“Terrorism is first and foremost a strategy, and you can’t defeat a strategy. So there’s no question it’s always going to exist,” said Horgan of Georgia State. “We can work to undermine and delegitimize terrorism, and we can work to make sure we don’t heighten the risk, but to confront the risk effectively we have to also be realistic about what we are actually facing.”

It is only natural for politicians to want to reassure a nation reeling from tragedy. Trump is not the only official offering comfort and promises to safeguard the country. On Monday, Hillary Clinton argued that “the barbarity we face from radical jihadists is profound” in her own speech. “The attack in Orlando makes it even more clear: We cannot contain this threat—we must defeat it.”

There’s no perfect political response to terrorism. Cautious, evidence-based ideas do not necessarily satisfy the role most citizens expect their leaders to play in the wake of a terrorist attack. Americans look to their representatives to be reassured, often demanding punishment for injustice. Those expectations make it all the more difficult to for political leaders to exercise the kind of restraint counterterrorism experts advise.

No politician wants to be accused of failing to take a terrorism threat seriously or appearing callous in the face of atrocity. President Obama has frequently been criticized on this count: His opponents portray him as unconcerned and prone to underestimating the danger posed by terrorism. But if politicians fuel fear and prejudice as they work to position themselves as capable leaders, or promise what they cannot deliver, their actions could end up making it harder for America to productively prepare for and respond to danger.  

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