President Obama, shortly before the Friday evening fracas at a Donald Trump rally in his hometown of Chicago, criticized the fractured Republican Party and reiterated his view that Republicans brought the dissonance upon themselves.

“We’ve got a debate inside the other party that is fantasy and schoolyard taunts and selling stuff like it’s the Home Shopping Network,” he told supporters at a fundraiser in Austin, before turning to the incendiary statements that Trump has made about Muslims and Latinos.

“And then you’ve got the Republican establishment -- they’re very exercised: 'We’re shocked that somebody would be saying these things. We’re shocked that somebody is fanning anti-immigrant sentiment or anti-Muslim sentiment. We’re shocked!'”

Violence splashed across the television screen Friday night like a horrific flashback from the 1960s, as fistfights and shoving broke out among thousands of supporters and opponents at a Donald Trump event in Chicago, drawing memories of police and protesters fighting in the streets of the same city during another political gathering in 1968.

Nothing about it was surprising.

What many had feared as Trump’s campaign has proceeded had finally happened on a large scale: A flammable brew of populist anger, campaign mismanagement, a candidate’s own provocative encouragement and protesters fighting back — quite literally — finally found its fuse. The explosion was predictable, given tensions in the country around its changing demographic face and economic displacement that has left many fearful and upset, receptive audiences for Trump’s surprisingly strong candidacy.

Chicago police "were not consulted" and "did not provide an opinion" on Donald Trump's decision to cancel a rally in Chicago, the department said Friday night.

The department made clear to the Trump campaign that "we were confident we had the proper amount of resources dedicated to the event," interim Supt. of Police John Escalante said in a news conference.

Escalante said 200 Chicago police officers were initially deployed to the event and an additional 100 were sent as a precaution upon word that the rally might be canceled.

Former presidential hopeful Ben Carson suggested that the frustrations of urban life can lead to protests like those at the canceled Donald Trump rally in Chicago on Friday.

College campuses are also breeding intolerance to opposing views, said Carson, who endorsed Trump earlier in the day.

"We need to recognize what's happening, particularly in a lot of our inner cities," Carson told Fox News' Sean Hannity. 

Marco Rubio tried to have it both ways Friday night, saying that the disturbances at Friday’s Donald Trump rally were due to organized, perhaps professional protesters, but that the GOP front-runner bears responsibility for a divisive message.

“We have reached a breaking point in our politics,” Rubio said in an interview on CNN.

The Florida senator said the protests that erupted at Trump’s Chicago rally were not “organic,” but he simultaneously faulted the message the businessman has put forward as divisive.

Ohio Gov. John Kasich, who has generally taken a kinder, gentler tone in this raucous GOP nominating contest, called for unity in response to Friday night's mayhem ahead of a scrapped Donald Trump event in Chicago.

"The seeds of division that Donald Trump has been sowing this whole campaign finally bore fruit, and it was ugly," Kasich said in a statement. "Some let their opposition to his views slip beyond protest into violence, but we can never let that happen. I urge people to resist that temptation and rise to a higher level."

Kasich appealed to Americans' sense of togetherness, saying, "We are great because we are a peaceful people who live by the rule of law. 

"Welcome to the general election."

That's the message the director of a major progressive group endorsing Bernie Sanders had for Donald Trump on Friday night after hundreds of protesters clashed with Trump supporters at a planned Trump campaign rally in Chicago.

Ilya Sheyman, executive director of MoveOn.org's political action group, blamed Trump for the evening's unrest in a statement issued to the group's members.

A CBS News reporter was detained by police while covering the turmoil at Donald Trump's canceled Chicago rally Friday night, the network said.

The detained reporter is Sopan Deb, who covers Trump for the network. CBS posted this statement at the bottom of its story on the Chicago upheaval:

"In the midst of reporting on this event, CBS News' Sopan Deb was detained by law enforcement. We are awaiting more information on the circumstances and will continue to update our report."