Story highlightsFallon appears to fight back tears in monologue on clashes in Virginia.

Late-night host calls out Donald Trump for delayed response to racism.

For more on late night comedy’s influence on culture and politics, watch CNN’s “The History of Comedy” Sundays at 10 p.m. ET/PT. Instead Fallon, at times appearing to fight back tears, spoke from the heart about Saturday’s deadly events in Charlottesville, Virginia.

While acknowledging that “The Tonight Show” is not political, Fallon opened up about the clashes in Charlottesville between white nationalists and counterprotesters.

“What happened over the weekend in Charlottesville, Virginia, was just disgusting,” Fallon said.

Fallon said he wondered how he would explain racism to his young daughters, who are 2 and 4, and paid tribute to Heather Heyer, who died after a car rammed into a group protesting the white nationalists.

“The fact that it took the President two days to come out and clearly denounce racists and white supremacists is shameful,” Fallon said.

Fallon was criticized last year for his light banter with then-presidential candidate Trump during an appearance on “The Tonight Show.” The late-night host was accused of not being critical enough of Trump and at one point even ran his fingers through Trump’s hair.

“They have a right to be mad,” Fallon told The New York Times in May. “If I let anyone down, it hurt my feelings that they didn’t like it.