The appeal is three dimensional. First, Trump says it how it is. A grim tradition has emerged since 9/11 of treating every terrorist attack like a mystery: politicians seem to wonder who did it and why.

Trump simply points the finger at radical Islamism. And while every other statesman sends “thoughts and prayers”, Trump talks about arming citizens and toughening up. In the aftermath of the Dallas shootings, he downplayed the race angle and put himself squarely behind the police.

Second, Trump’s ego offers the hope of action. Obama has allowed his presidency to be cast as reactive – responding to crises in a cool way that is temporarily reassuring but begs the question “what was he doing to prevent this from happening in the first place?” Trump’s constant tweeting about the need to smarten up suggests vigilance.

And, third, Trump’s policies contrast starkly with the suggestion that terrorism is something Americans just have to live with. He will build a wall to keep the illegals out. He will stop Muslims from migrating to America.