Someone dares call it treason. Hillary Clinton used the occasion of the New York-area bombings to accuse Donald Trump of providing “aid and comfort” to ISIS.

This speaks both to her desperation as polls show a tightening race and her foolish misunderstanding of what drives ISIS and other Islamic radicals.

Clinton makes it sound like ISIS fighters are disaffected members of a swing-state focus group who, as soon as they hear an offensive statement from Donald Trump, prepare the next attack.

If Hillary really believes Trump is a “recruiting sergeant” for terrorists, she has a thin understanding of human motivation. It takes something very powerful to convince a young man to risk life and limb fighting for a terror group that is hunted and bombed wherever it gains a foothold. That something isn’t the ephemera of an American presidential campaign; it is religion.

ISIS is an apocalyptic cult. As Graeme Wood wrote in a widely noted essay in The Atlantic last year, “Virtually every major decision and law promulgated by the Islamic State adheres to what it calls, in its press and pronouncements, and on its billboards, license plates, stationery, and coins, ‘the Prophetic methodology,’ which means following the prophecy and example of Muhammad, in punctilious detail.”

It is tempting, Wood writes, to consider jihadists “modern secular people, with modern political concerns, wearing medieval religious disguise,” when in reality ISIS is inexplicable outside of its “sincere, carefully considered commitment to returning civilization to a seventh-century legal environment, and ultimately to bringing about the apocalypse.” In other words, Donald Trump — or any other American politician — is beside the point.

Radical Islamists have maintained a murderous enmity to the United States across presidencies. What did Hillary’s husband do to incite Islam? Yet al-Qaida nearly sank a U.S. destroyer on his watch and hatched the Sept. 11 plot. George W. Bush insisted that Islam is a religion of peace, and Barack Obama steadfastly refuses to use the word “Islam” in connection with the word “terrorism.” Yet there is no evidence that al-Qaida or ISIS relented in response to their carefully selected diplomatic words.

The left has a habit of calling things it doesn’t like “recruiting tools” for terrorists. We were told that the Iraq War was a recruiting tool, even though shortly after President Obama “ended” the war, ISIS established a caliphate straddling Iraq and Syria. We were told that Guantanamo Bay was a recruiting tool, even though the ISIS threat has grown as President Obama has moved to shut down the facility.

A few recruiting videos have indeed featured Trump. It’s hard to believe, though, that young Muslim men around the world are becoming terrorists because they take exception, for example, to Trump’s proposed temporary ban on Muslim travel to the United States. One video from a pro-ISIS group earlier this year appeared to use a clip from Trump — saying Brussels is “an absolute horror show” — purely to attract media attention.

None of this is to say that Trump’s inflammatory statements are correct or wise. But the best recruiting tool that ISIS has, besides its twisted religious vision, is its success on the ground. That’s why voters should want to hear a serious plan to defeat ISIS from both Trump (whose plan is secret) and Hillary (whose plan is a nebulous version of the status quo).

We shouldn’t fool ourselves that the right choice of words or immigration policies will mitigate the threat from ISIS or similar groups. The source of their hatred is much deeper than that. As an ISIS magazine put it, “The fact is, even if you were to stop bombing us, imprisoning us, torturing us, vilifying us, and usurping our lands, we would continue to hate you because our primary reason for hating you will not cease to exist until you embrace Islam.”

Short of that, there is no choice but to fight on — and reject delusion.

Rich Lowry can be reached via e-mail: comments.lowry@nationalreview.com.