Donald Trump speaks during a joint statement with Mexico's President Enrique Pena Nieto in Mexico City on Aug. 31. (Marco Ugarte/Associated Press)

Farah Pandith was a political appointee in the George H.W. Bush, George W. Bush and Barack Obama administrations. She is an adjunct senior fellow at the Council on Foreign Relations.

While serving under Secretary Hillary Clinton as the State Department’s first special representative to Muslim communities, I had a chance to visit with Muslims in almost 100 countries. This summer, as Donald Trump’s anti-Muslim rhetoric dominates the headlines, I think back to one encounter, both powerful and troubling, that I had with a community in Cambodia.

We had driven for hours through the jungle on a hard-packed dirt road. Finally we reached a village — just a few modest buildings among the trees, including a simple mosque with whitewashed mud walls and a dirt-pressed floor. Sandals lined the walls, and straw mats served as our seats. Dozens of barefoot residents of this Muslim community crowded around.

I sat down on the floor beside a translator, and our conversation began. Audience members asked questions that, unfortunately, I had often heard in other communities. Are Muslims real U.S. citizens? Do Americans spit on you when they hear you’re Muslim? Can Muslims wear headscarves in the United States? Can they pray, and if so, where? Wasn’t 9/11 a setup by Jews to frame Muslims? How was I allowed to serve in government if I was a Muslim?

And then came a question I hadn’t expected: Does Terry Jones really represent America?

Jones had been an obscure Florida preacher with a flock of fewer than 50. He first gained notoriety in 2010 when he announced his plan to burn Korans on the anniversary of the Sept. 11, 2001, attacks. A year later, he did burn the Muslim holy book, provoking international outrage and unrest that left dozens dead. Most Americans had forgotten all about him, if they had heard of him at all. But here in this remote pocket of Cambodia, the inhabitants had not only heard of him and remembered him by name. They also thought he spoke for America.

Today, instead of an obscure preacher openly disparaging Muslims and Islam, it’s the leader of one of the two main U.S. political parties, a man supported by about 40 percent of the population. He doesn’t burn the Koran. Rather, he accuses a sitting president of having “founded” the so-called Islamic State terrorist organization. He denigrates the Muslim mother of a fallen U.S. soldier. He proclaims Islam a dire threat to the homeland. He proposes a ban on Muslims entering the United States. And, unlike Jones’s words, his are endlessly discussed in the mainstream media worldwide, week after painful week.

The United States won’t soon repair the damage done by Trump to its image among Muslims. We’ve spent billions since 9/11 trying to convey a clear picture of who we are as Americans and to convince Muslims that the United States is not “at war” with them.

President George W. Bush placed a Koran in the White House Library for the first time in U.S. history and created an envoy to the Organization of Islamic Cooperation. He visited U.S. mosques — right after Sept. 11 and later to rededicate the mosque where Dwight D. Eisenhower had laid the cornerstone . President Obama followed up his 2009 Cairo speech with an array of initiatives to bolster trust and engagement with Muslims. At a local level, our embassies have devoted countless hours to convincing Muslim populations that the United States believes in equality, religious freedom and respect.

Now, thanks to Trump, any goodwill we have generated has been largely diminished. In rural villages such as the one I visited in Cambodia and in large cities around the globe, Muslims will point to Trump as irrefutable evidence that the United States hates them and is at war with Islam.

This impression has real-world consequences that will translate directly into more terrorist attacks globally and more lives lost here at home. After spending more than a decade speaking to tens of thousands of Muslims, I have little doubt that the Islamic State and other groups will recruit more Muslim youths, thanks to Trump’s anti-Muslim tirades and the consequent widespread belief that the United States is perpetrating a war against Islam. Indeed, the terrorists explicitly appeal to supporters and potential recruits by touting the war they are fighting against an America resolutely hostile to Muslims.

Trump may lose in November. But his bigoted words about Islam and his mythical narratives about the formation of the Islamic State will require hundreds of millions of dollars and many decades to neutralize.