In his final press conference as president, Barack Obama warned that economic and other forces could further divide Americans, and sent messages anew to Donald Trump, particularly that he could re-enter the political arena if “our core values may be at stake.”

Less than 48 hours before he will cede all powers of the presidency to Trump, the 55-year-old Obama, with more salt than pepper atop his head, showed flashes of the optimistic candidate who toppled both Hillary Clinton and Sen. John McCain, R-Ariz., during the 2008 presidential campaign. But by the end of the session, his concerns about the next four years appear to show through.

“I believe in this country. I believe in the American people,” Obama said. “I believe that people are more good than bad.”

The president pointed to economic inequality as his biggest worry about the future of the country, saying “if we are not investing in making sure everybody plays a role in this economy, the economy will not grow as fast.” An even wider gap between haves and have nots would “also lead to further and further separation between us as Americans — not just along racial lines.”

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“I mean, there are a whole bunch of folks who voted for the president-elect because they feel forgotten and disenfranchised,” he said. “They feel as if they’re being looked down on. They feel as if their kids aren’t going to have the same opportunities as they did.”

In one of a handful of final thinly veiled pieces of advice for Trump he dropped Wednesday, Obama said that “you don’t want to … have an America in which a very small sliver of people are doing really well, and everybody else is fighting for scraps.” Under those conditions, he warned, “racial divisions get magnified, because people think, well, the only way I’m going to get ahead is if I make sure somebody else gets less. … That’s not a good recipe for our democracy.”

Obama, in a striking scene that showed he is attuned to Trump and his team threatening to kick the White House press corps out of the White House, began the nearly hour-long session, by endorsing efforts by the presidential press corps to remain in their workspace in the West Wing.

“I spent a lot of time … in my farewell address talking about the state of our democracy,” Obama said. “It goes without saying that essential to that is a free press. That is part of how this place, this country, this grand experiment of self-government has to work. It doesn’t work if we don’t have a well-informed citizenry.

“So America needs you and our democracy needs you,” Obama added. “We need you to establish a baseline of facts and evidence that we can use as a starting point for the kind of reasoned and informed debates that ultimately lead to progress.”

But it seemed the need to deliver that kind of pro-press freedom lecture, and the many uncertainties regarding whether Trump will leave in place any of his top accomplishments, has left the candidate who ran on hope with a less-optimistic view of the country’s future than he possessed eight years ago.

“At my core, I think we’re going to be OK,” Obama said in a less-than-optimistic assessment about where the country is headed. “We just have to fight for it. We have to work for it. And not take it for granted.”

Obama then offered telling final words for the reporters and photographers in the briefing room: “Good luck.”

Meantime, the outgoing president again signaled he intends to follow the tradition of most former U.S. presidents and remain on the sidelines of policy debates out of deference to the sitting chief executive. But he also had a message for Trump: Overstep on certain issues and I’ll return to politics.

On the normal “back-and-forth” in Washington on issues like tax cuts, the president said citizen Obama won’t weigh in. Then came the warning from a man who won two presidential elections and will depart office with approval ratings in the low-60s, compared to Trump’s 40-something numbers.

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“But there’s a difference between that normal functioning of politics and certain issues or certain moments where I think our core values may be at stake,” a somber-faced Obama said. “I put in that category if I saw systematic discrimination being ratified in some fashion. I put in that category explicit or functional obstacles to people being able to vote, to exercise their franchise.”

Also on that list is any Trump-ordered program to, as the incoming POTUS has put it, “round up kids who have grown up here and for all practical purposes are American kids, and send them someplace else, when they love this country. … I think would be something that would merit me speaking out.”

But would he feel so strongly that he might seek some kind of elected office? “It doesn’t mean that I would get on the ballot,” he said.

Earnest: Obama ‘Reserves the Right’ to Speak Out

Meanwhile, one day after his own last go-round in the Brady briefing room, Obama’s top spokesman, Josh Earnest, was asked about a recent GQ article that explored what kind of relationship Obama would have with Trump.

“President Obama is hopeful that he can do the same thing President [George W.] Bush did,” Earnest told Roll Call during a Christian Science Monitor-sponsored breakfast. “The president also is reserving the right, if some basic values and norms are being violated, to speak out.”

Obama and his senior staff have talked throughout his final year about his appreciation for how Bush handled the transition period between their administration, as well as how the 43rd president has spent his post-White House life. For the most part, Bush has remained silent. Obama believes the country benefits most when former presidents give the sitting one the space to “execute their vision,” Earnest said.

Will GOP Blockade of Garland Leave ‘Scar’ on Senate?

Senate Republicans’ refusal to give former Supreme Court nominee Merrick Garland a hearing or floor vote will leave a permanent “scar” on the chamber, Earnest said, adding the blockade will undercut the GOP’s arguments for Trump’s eventual nominee.

On his penultimate day as Obama’s White House press secretary, Earnest said the Republican tactics had a negative impact on the country, its criminal justice system and “our democracy.” But for Republicans, he said, “it turned out to be good politics.”

Senate Democrats will have the option of launching a filibuster of whomever Trump nominates for the ninth high court seat. Even if they do – which inevitably would draw hails of hypocrisy from Republicans – Earnest launched a preemptive defense. Should that nominee reach the chamber floor, it would mark a major difference from how the GOP handled Garland because the Judiciary Committee would have held hearings and a vote, he said.

Quote of the Day

“Let me start off by saying that I was sorely tempted to wear a tan suit today for my last press conference. But Michelle, whose fashion sense is a little better than mine, tells me that’s not appropriate in January.” –Obama, referring to a beige suit he wore to a briefing in August 2014, which created a social media uproar.

Contact Bennett at johnbennett@cqrollcall.com. Follow him on Twitter @BennettJohnT.