Clinton’s innovation was the pious and benevolent declaration that Islam was not synonymous with terror.

“We both know it is profoundly wrong to equate Palestinians, in particular, and Islam, in general, with terrorism or to see a fundamental conflict between Islam and the West,” he said in Gaza in 1998. “For the vast majority of the more than one billion Muslims in the world, tolerance is an article of faith and terrorism a travesty of faith.”

Such statements were well-intentioned, trying to avoid an unfortunate and unfair association between the religion and violence. But they also laid the groundwork for Clinton’s successors to begin explaining Islam to Muslims.

George W. Bush made that possibility concrete following September 11. Even to his critics, Bush’s speeches about Islam remain among the finest moments of his presidency. On the one hand, Bush wanted to make sure that non-Muslims avoided demonizing the whole religion. On the other hand, doing so necessitated Bush making his own assertions about Islam.

“These acts of violence against innocents violate the fundamental tenets of the Islamic faith. And it's important for my fellow Americans to understand that,” Bush said on September 17, 2001. “The face of terror is not the true faith of Islam. That's not what Islam is all about. Islam is peace. These terrorists don't represent peace. They represent evil and war.”

This was a view he repeated over the years, even as other members of his administration spoke of a “crusade,” and the U.S. government adopted policies that infringed on Muslims’ civil liberties. In 2006, for example, Bush said that “radical Islam [was] the perversion by a few of a noble faith into an ideology of terror and death.”

Will McCants pinpoints the trouble with such statements. Islam, like Christianity, defies such easy categorizations. “President Trump’s predecessors often called Islam a religion of peace. Candidate Trump often associated Islam with war,” McCants writes. “The truth is that Islam, like other ancient faiths, contains multitudes.”

Obama represented the apotheosis of the tendency to explain Islam to its own adherents. One June 4, 2009, just months into his first term, the president delivered a major speech in Cairo about U.S. relations with Muslims. It was a speech that only Obama could have given: as successor to Bush, widely disliked in the Muslim world; as a man who had spent part of his childhood in Indonesia, and whose name was Barack Hussein Obama; and as a politician possessed of a cockiness sometimes unto arrogance.

Like Dwight Eisenhower, he extolled the long-running Muslim presence in the U.S. Like Reagan, he pointed a finger at Muslim terrorists as killing mostly other Muslims. But he also instructed on the proper way for Muslims to approach faith:

Among some Muslims, there is a disturbing tendency to measure one's own faith by the rejection of another’s. The richness of religious diversity must be upheld—whether it is for Maronites in Lebanon or the Copts in Egypt. And fault lines must be closed among Muslims as well, as the divisions between Sunni and Shia have led to tragic violence, particularly in Iraq.

Obama’s goal, he told my colleague Jeffrey Goldberg years later, was “to persuade Muslims to more closely examine the roots of their unhappiness.” He acknowledged that the speech had not succeeded: “I was hoping that my speech could trigger a discussion, could create space for Muslims to address the real problems they are confronting—problems of governance, and the fact that some currents of Islam have not gone through a reformation that would help people adapt their religious doctrines to modernity.”