In rebuke to politicians like Donald Trump, Obama presented Islam as an essential part of the nation’s heritage, going back to Muslim slaves brought to the British colonies and running through Thomas Jefferson’s Virginia Statute for Religious Freedom up to Fazlur Rahman Khan, who designed two of Chicago’s tallest skyscrapers. And he spoke emotionally about mail he received from Muslim American children and parents who felt persecuted and unsafe.

“We’re one American family. And when any part of our family starts to feel separate or second-class or targeted, it tears at the very fabric of our nation,” he said.

Obama’s visit comes at a time of particular tension for the American Muslim community. Advocates report an increasing number of Islamophobic incidents, which are mirrored in the Republican presidential race. Donald Trump endorsed the suggestion of a registry of Muslims in the U.S., and he suggested barring Muslims from entering the country—even citizens returning from abroad. Other candidates have suggested a link between refugees fleeing Syria and Iraq and terrorism. Although there was a spate of attacks and incidents against Muslims after 9/11, the support of President George W. Bush made them feel that those attacks were mostly from the fringe.

“With the recent spike in anti-Muslim sentiment nationwide and especially in the last few months since the Paris terror attacks and the San Bernardino attacks… there’s never been this level of fear and apprehension in the American Muslim community before,” said Ibrahim Hooper, spokesman for the Council of American-Islamic Relations. “Unfortunately now thanks to people like Donald Trump and Ben Carson, it’s directly in the mainstream.”

Against that background, leaders welcomed Obama’s visit as an important signal of the nation’s leader rejecting those attacks—and a message to Muslims that they belong in the United States.

“It means to us that we are a part of this society,” said Riham Osman, a spokeswoman for the Muslim Public Affairs Committee.

Obama took pains to condemn Islamophobic rhetoric during his State of the Union address in January. “When politicians insult Muslims, whether abroad or our fellow citizens, when a mosque is vandalized, or a kid is called names, that doesn’t make us safer,” he said. “That’s not telling it like it is. It’s just wrong. It diminishes us in the eyes of the world. It makes it harder to achieve our goals. It betrays who we are as a country.”

On Wednesday he responded to critics—especially Republican contenders to replace him in the White House—who complain that he won’t label Islamic terrorism as such, saying demands to label by religion only play into extremist propaganda.

“I often hear it said that we need moral clarity in this fight. And the suggestion is somehow that if I would simply say, ‘These are all Islamic terrorists,’ then we would actually have solved the problem by now, apparently,” he said. “Let’s have some moral clarity: Groups like ISIS are desperate for legitimacy.... We must never give them that legitimacy. They’re not defending Islam. They’re not defending Muslims.”