The fundamental difference between Obama and Trump on issues related to Islamist extremism (apart from the obvious, such as that, unlike Trump, Obama a) has killed Islamist terrorists; b) regularly studies the problem and allows himself to be briefed by serious people about the problem; and c) is not racist or temperamentally unsuitable for national leadership) is that Trump apparently believes that two civilizations are in conflict. Obama believes that the clash is taking place within a single civilization, and that Americans are sometimes collateral damage in this fight between Muslim modernizers and Muslim fundamentalists.

In one conversation, parts of which I’ve previously recounted, Obama talked about the decades-long confrontation between the U.S. and communism, and compared it to the current crisis. “You have some on the Republican side who will insist that what we need is the same moral clarity with respect to radical Islam” that Ronald Reagan had with communism, he said. “Except, of course, communism was not embedded in a whole bunch of cultures, communism wasn’t a millennium-old religion that was embraced by a whole host of good, decent, hard-working people who are our allies. Communism for the most part was a foreign, abstract ideology that had been adopted by some nationalist figures, or those who were concerned about poverty and inequality in their countries but wasn’t organic to these cultures.”

He went on to say, “Establishing some moral clarity about what communism was and wasn’t, and being able to say to the people of Latin America or the people of Eastern Europe, ‘There’s a better way for you to achieve your goals,’ that was something that could be useful to do.” But, he said, “to analogize it to one of the world’s foremost religions that is the center of people’s lives all around the world, and to potentially paint that as a broad brush, isn’t providing moral clarity. What it’s doing is alienating a whole host of people who we need to work with us in order to succeed.”

Does Obama go too far in avoiding the terms “radical Islam” or “violent Islam”? This question represents a not-unreasonable basis for an interesting debate. However, given the realities of the battlefield—that most of the fighting against ISIS is done by Muslim-majority states, and Muslim organizations, and that the leaders of these entities would rather not see the U.S. overgeneralize its description of the fight—then it seems to me, at least, that Obama’s semantic prudence is justifiable.

Donald Trump, I believe, is not capable of making the sort of analysis Obama has made about the splits within Islam. Nor has refuted Obama’s analysis in a cogent fashion. But this is not Trump’s main sin; his main sin is to refuse to listen to experts on counterterrorism, including experts in the U.S. military and intelligence community, who argue that he is helping ISIS by demonizing Muslims. Abu Bakr al-Baghdadi, the so-called caliph of Islamic State, argues that there is no place in the West for a devout Muslim. Donald Trump often gives the impression that he shares this view, and that he is advancing the cause of ISIS, by endorsing its premise that the struggle in which it is engaged is, in fact, civilizational.

None of this is meant to be an argument that Obama does enough, or does enough of the right things, in the struggle against ISIS. I could (and will!) write a critique of the administration’s tactical approach, particularly as it relates to Syria. And Obama could bring more emotional intelligence to bear on this problem: He is eloquent in condemning the fearmongers, but he sometimes fails to acknowledge the legitimate fears of non-racist, non-paranoid Americans who would prefer not to be killed by terrorists acting in the name of Islam. The United States is under intermittent attack from an organization called the Islamic State, which, as Graeme Wood has pointed out in this magazine, represents one, extreme, branch of Islam. There is no point in trying to convince Americans that what is happening is not happening. But neither is there a point in encouraging hysteria and division.

Privately, Obama expresses the deepest loathing for ISIS and other radical Islamist groups. ISIS, he has noted, stands for—quite literally—everything he opposes. Nevertheless, his approach to the challenge of Islamist terrorism is sometimes emotionally unsatisfying; it is sometimes insufficient to the challenge; and he himself is sometimes too fatalistic about the possibility of change in the Middle East.

Donald Trump’s approach, on the other hand, is simply catastrophic.