Jonathan Ernst / Reuters

On Monday morning, Donald Trump claimed to his millions of followers on Facebook and Twitter that “Hillary Clinton's weakness while she was Secretary of State has emboldened terrorists all over the world to attack the U.S., even on our own soil.” Many of his fans celebrated the attack on the Democratic nominee. I invite them to give his words a closer look. Those who do will find two reasons for concern.

First, it is important for the president and the American people to understand what motivates Islamist terrorism, an ongoing threat to our safety. Clarity on that subject really could have life or death consequences. And if we take Trump at his word, he believes something that is obviously false: that the secretary of state is a determining factor in whether mass murderers intent on killing Westerners act or not—indeed, Trump’s words suggest a belief that at least one person who already killed Americans on our soil wouldn’t have done so but for Hillary Clinton’s tenure.

If he believes this he is woefully unprepared to combat terrorism.

Now, I don’t think Trump actually believes his own words. It would take ignorance far greater than his to believe that Islamist terrorist attacks against the United States, a phenomenon illustrated most memorably on September 11, 2001, turn decisively on “weakness” by the secretary of state from 2009 to 2013.

But if he is innocent of being too ignorant about the reality of terrorism to be president, then he is guilty of trying to mislead Americans about the nature of terrorism for political gain. And that is execrable. Whether Republicans or Democrats, liberals or conservatives, Americans share a common interest in clarity on the matter of what causes terrorism and how best to fight it. Disagreements on that subject are totally legitimate. Lying about that subject is not—it undermines America’s ability to understand and fight terrorism for the selfish gain of a politician. All politicians lie, but that sort of lie is especially pernicious and shameful.

And there is more.

Even if we treat Trump’s comments as yet another instance of his abandoning the literal meaning of words—even if we take him as trying to convey only that Hillary Clinton was a bad secretary of state—we arrive at another worrisome conclusion about Trump.

Understanding it requires a bit of background.

When President Obama appointed Hillary Clinton as secretary of state, Donald Trump declared that Obama was “doing great” and that “I think Hillary Clinton is a great appointment.”

Later, during Clinton’s tenure as secretary of state, Trump gushed about how much he liked Clinton and how harding working she was, among other words of praise:

Even after the Benghazi attack, Trump was praising Secretary of State Clinton:

At various times, Trump has tried to explain away this praise. For example, he told Jimmy Kimmel that due to his business interests he always spoke highly of politicians, prompting the late night host to comment that Trump was saying he is “full of shit.”

Trump agreed!

But calling Trump “full of shit” lets him off too easily here. If we take Trump at his word, he wasn’t being a typical businessperson saying nice things about a politician while secretly disagreeing with them on taxes or immigration policy. If we take Trump at his word, he was falsely praising Clinton and her work as secretary of state even as he believed it was emboldening terrorists to murder Americans! That is the implication of the story he is now telling us.

Now, there’s no way to know what is really going on in Trump’s head.

But it’s hard to reconcile all his contradictory comments and behavior without concluding that, one way or another, Trump treated his own business or political interests as more important than American democracy’s collective effort to stop terrorism. And any way you tell it, Trump demonstrated a willingness to go on national television and blatantly lie to millions of Americans on this grave, life-or-death topic. Why does anyone trust Trump, or believe he should be entrusted with the presidency? Over and over, he shows with his actions that he is dangerously unfit.

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