As per report in a forceful return to the political fray aimed at firing up Democratic voters ahead of key elections and since leaving office, the 44th United States president has pointedly avoided direct criticism of his successor, making a calculated effort not to utter Trump's name, but on Friday the gloves came off.
"In fact, the best explanation of President Trump's victory are the "results" of the Obama Presidency!"
The Republican National Committee, for its part, responded to Obama's speech by saying, "President Obama stepped back into the spotlight to make the case that our country is on the wrong track".
In a now infamous comment following the clash of white supremacists and counter-protesters, which saw counter-protester Heather Heyer killed when a Nazi-sympathiser drove a auto into a crowd, Mr Trump said there were "some very fine people on both sides".
"He is a symptom, not the cause". He said, "Trump is just capitalising on resentments that politicians have been fanning for years".
"If you don't like what's going on right now, and you shouldn't - do not - complain", Obama said.
Exhorting students to vote in the November midterm elections and presenting a Democratic message, the former home-state president repeatedly chastised the current state of GOP-led politics as not "normal", including an anonymous White House administration official's recent description of a group running government in spite of an impetuous Trump.
Obama will hit the campaign trail on Saturday, appearing at a campaign event in southern California before heading to OH next week and to IL and Pennsylvania later in the month.
"We're supposed to stand up to discrimination", Obama said.
"If we don't step up, things can get worse", Obama warned the crowd in Anaheim on Saturday.
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"And we're sure as heck supposed to stand up to Nazi sympathizers", Obama said, referring to Trump's comment that there was blame on "both sides" ata white nationalist rally past year in Charlottesville, Va. "And, in a healthy democracy, it doesn't work", Obama said. In one of the speech's more timely soundbites, Obama blasted his successor's fierce and frequent attacks on the press.
Barack Obama with sister Auma Obama and President Uhuru Kenyatta when he visited Kenya on Sunday, July 15 since he finished his presidential term.
Republicans say they aren't anxious. Aides close to Obama have said he's bit his lip, wanting to avoid an ugly tit-for-tat and to stay above the fray.
"The biggest threat to our democracy ... is not one individual, it is not one big super PAC billionaires", he said.
"It's a consequential moment in our history", Obama said. "I found he's very good". [LAUGH] Sometimes I'll be in my office and I'm doing my work and I'll see this, her like scurrying, And I gotta get up and run before she does her thing.
Trump told supporters in Montana on Thursday that Republicans needed to maintain control of Congress to stave off possible impeachment proceedings against him, although Democrats have played down any discussion of that approach.
The former president, who was accepting an ethics award from the school, said voting in this year's midterm elections was the antidote to stopping the fear and division that Trump has stoked.