"The fact of the matter is this is hateful. It is racist. It is bigoted. It is xenophobic. It represents a kind of Jim Crow with hairspray and a blue suit," Brooks told CNN's Wolf Blitzer on "The Situation Room." "Let's not underestimate what we're dealing with. This is a very, very ugly moment in America."
But Brooks said he doesn't hold anything against Americans who support Trump.
"I don't blame the people -- American citizens -- for their economic anxieties and a sense of desperation. The fact that their grasping at straws and they grasped onto a bigoted, demagogic billionaire speaks to their desperation, not necessarily his appeal or the strength of his platform," he said.
CNN has reached out to the Trump campaign for comment, with no response.
The billionaire's rallies have turned increasingly violent in the past week as supporters have clashed with protesters. Trump was forced to cancel a rally in Chicago
over the weekend and was given a scare when a protester rushed the stage Saturday
And a former Breitbart reporter filed an assault charge
against Trump's campaign manager Corey Lewandowski, alleging he yanked her violently from Trump last Tuesday.
"The fact of the matter is he's engaged in rhetoric that represents a kind of apologetics, if you will, of violence," Brooks said.
Cumberland County Sheriff's Office in North Carolina said Monday they are weighing whether to press charges against Trump for inciting
a riot during that rally where the protester was sucker punched by a 78-year-old white man. Trump has said he is considering paying the legal fees
for the supporter charged with assault.
Trump campaign spokeswoman Hope Hicks flatly rejected the premise of the investigation into Trump's role in the violent altercation.
"It is the protesters and agitators who are in violation, not Mr. Trump or the campaign," Hicks said Monday in a statement.
Hicks added that Trump's speech was "extremely well thought out and well received" and instead focused on the role of protesters, who she said "in some cases ... used foul language, screamed vulgarities and made obscene gestures, annoying the very well behaved audience."
Brooks believes Trump's behavior is "contemptible" but will "leave that for the prosecutors in North Carolina to determine."
He added there "absolutely" is a racial aspect to business mogul's increasingly violent rallies.
"When you call Mexicans rapists, when you use code words like 'thug,' where you suddenly can't distance yourself from the Klan. The fact of the matter is we've been in this ugly movie before. In the 1920s the Klan combined an anti-immigrant sentiment in the country with a kind of un-American patriotism with a venue of Christianity," Brooks said.
Blitzer pointed out that Trump eventually did disavow the Klu Klux Klan.