"He is just capitalizing on resentment that politicians have been fanning for years", he said. "Other voices (will) fill the void".
"I'm sorry, I watched it, but I fell asleep", he said during a campaign trip to the Dakotas.
He went on to attack Trump by name.
Earlier this week, an unnamed White House official penned a New York Times opinion piece, claiming the president's worst impulses were tempered by "adults in the room", who ensured he did not act to the detriment of the USA on issues such as foreign policy.
While in his speech, Obama did not bash Trump directly, he did make some digs that could only be attributed to the current president.
"It's radical. It's a vision that says the protection of our power and those who back us is all that matters even when it hurts the country".
Former President Barack Obama's remarks in his home state of IL came after a almost two-year absence from the political stage, during which he avoided directly criticizing Trump and made a calculated effort not to utter his successor's name.
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Police also released an image of a counterfeit perfume bottle after tests found it contained a "significant amount" of Novichok. Metropolitan Police Assistant Commissioner Neil Basu said there is no suggestion that they have since returned to the UK.
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In the second semi-final of the day, Djokovic holds a dominant 14-2 head-to-head record over Kei Nishikori . Osaka becomes the first Japanese woman in a Grand Slam semifinal since Kimiko Date at Wimbledon in 1996.
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Just hours later, the UN Security Council will also meet at Washington's request, also to discuss Idlib. Iran wants to keep its foothold in the Mediterranean state neighbouring Israel and Lebanon.
But instead of showing up to vote for the Democrat, they hoped their folks would show up to make sure Obama's party was not put back in the majorities in Congress.
Obama shared the billing with seven Democratic candidates in competitive U.S. House districts across California.
However, given Obama's less-than-stellar track record at unity - millions of Americans would argue Obama is directly responsible for much of today's division - Sen. "That unfortunately has been a spiral that we have been on for the last couple of years".
"When you hear how great the economy's doing right now, let's just remember when this recovery started", he said, recalling that he had inherited a risky economic downturn and left office amid a recovery. In the social media targeted clip, he said that "basic norms and principles" have been "increasingly violated" and pushed young people to get out and vote.
Obama told a large and enthusiastic crowd in Anaheim, California - in the traditionally Republican stronghold of Orange County - that the nation was "in a challenging moment".
"I wish he had gone a little harder on Trump", said Lee Rice, 73, an electrician from Oakdale in California's central valley. "As a fellow citizen, not as an ex-president", he said, "but as a fellow citizen, I am here to deliver a simple message and that is that you need to vote because our democracy depends on it". Obama's point is that this, while less abnormal than Trump's deranged-emperor routine, is not normal, either.
Following his California visit, Obama will travel to OH next Thursday for an event for Richard Cordray, the Democratic gubernatorial candidate in OH, and he is also slated to headline a campaign event in Pennsylvania later this month, and a NY fundraiser for the National Democratic Redistricting Committee, an organization led by former Attorney General Eric Holder, Obama's longtime friend.