We’re one terrorist attack away from Donald Trump doing something really crazy.

Brian Beutler today makes the “dispassionate” case for why we should be pessimistic about Trump’s presidency, arguing that his discriminatory refugee and immigration ban has already left “a permanent scar on the country’s credibility” and that there is more where that came from. Beutler is right in warning liberals to resist the kind of hyperbole that characterized the GOP’s unhinged response to Barack Obama, lest they discredit themselves. But I think there is some use, too, in briefly sketching an alarmist case for why we should not only be pessimistic about the future of the Trump administration, but deeply worried.

We know that the gravity of the office will not restrain him, as some had hoped. Neither will establishment figures like Chief of Staff Reince Priebus, who has apparently been swiftly muscled out by former Breitbart head Steve Bannon, newly inducted to the National Security Council. We know that Trump’s incompetence is only matched by his malevolence—that he has no compunction targeting some of the planet’s most vulnerable people, and that he is using executive orders with all the care and precision of a giant vindictive child. We know that he has shown little interest in broadening his appeal beyond his revanchist base, and that his habit is to double down on his mistakes and wildly pillory the media in response. Lost in all the furor surrounding the Muslim ban, for example, was the fact that the White House neglected to specifically cite Jewish victims on Holocaust Remembrance Day. Instead of simply correcting its statement, the administration trotted Priebus out onto the Sunday shows to defend it. He claimed that it addressed “everyone’s suffering in the Holocaust including, obviously, all of the Jewish people.” As many have noted, including Senator Tim Kaine, this is borderline Holocaust denialism.

As Beutler wrote, the institutions of civil society responded with alacrity to Trump’s Muslim ban, ensnaring his executive order in the courts. But the institutions of government are withering, starting with the moribund and morally decrepit Republican Party, the wound that allowed Trump to enter the body politic and hijack it. Meanwhile, the Western world is being buffeted by immense forces, from the fallout from the 2008 financial crisis to upheaval in the Middle East—the very forces that propelled Trump to the White House and continue to upend liberal democracy as we know it. The lesson of the 2016 election is that the system failed us utterly. If President Trump can happen, anything can happen.

All of this is to say that there’s a lot of gasoline lying around and it won’t take much to spark it. This is not to say we’re looking at some imminent version of the Reichstag Fire. Like everyone else, I took heart from the demonstrations at JFK and around the country; it was evidence that America is full of good people and that we are not doomed to some Trumpian dystopia. But just consider what would have happened if the terror attack in Quebec City had occurred in the United States (even if the attack targeted Muslims). With the ban already in place, wouldn’t such an attack become instantly politicized? Would such an attack not justify the ban in the eyes of the Trump administration, and give it grounds to expand it? Can anyone say, with any certainty, that we wouldn’t see tanks in the streets? I don’t think we should succumb to hysteria. But should we be afraid? Absolutely.

Update: The Trump administration is indeed using the attack to justify its immigration ban—even though the lone suspect so far is a French-Canadian.