James defended the protests at NFL games on Sunday in response to Trump attacking players through the weekend for kneeling during the anthem to protest racial injustice.
"First of all, I salute the NFL, the coaches, the players, the owners, the fans. Everyone had any association with the NFL was unbelievable," James told reporters at NBA Media Day. "There was no divide. Even from that guy that continues to try to divide us as people.
"He used the sports platform to divide us. Sports is so amazing, what sports can do for everyone, no matter shape, size, race. It brings people together like no other. I'm not going to let one individual no matter the power, the impact he or she should have ever use sport as a platform to divide us. The people run this country, not one person. And damn sure not him."
Trump called for the NFL to "fire or suspend" those who kneel during "The Star-Spangled Banner."
"It's powerful what all these athletes are doing," James said. "It's not about the disrespect of our flag and the military that's made this world free. ... It's about equality."
James acknowledged he has not considered taking a knee when the NBA's regular season starts up again next month, but he plans to continue speaking out.
"I can look myself in the mirror and say that I want the best for the American people -- no matter what skin color, race. No matter how tall, athletic you are or whatever the case may be," James said.
After Trump said on Saturday the Golden State Warriors were not welcome to the White House to celebrate their 2017 NBA championship, James took to social media to denounce the president: "U bum @StephenCurry30 already said he ain't going! So therefore ain't no invite. Going to White House was a great honor until you showed up!"
James said he did not regret the tweet and said referring to someone as a bum was not what he would define as name-calling.
"If you voted for him, you may have made a mistake," James said. "Can we sit up here and say I'm trying to make a difference? I want the best for the American people no matter the skin color, the race. We know this is the greatest country in the world. We still have problems, just like everybody else. ...
"As I have this platform, I will lend my voice, my passion, my money to let these kids know there is hope, greater walks of life. No one individual can stop your dreams from being a reality."
Still-unsigned quarterback Colin Kaepernick drew national attention last season while playing for the San Francisco 49ers when he knelt during the national anthem as a protest against racial injustice.
"I salute Colin for being as powerful as he was," James said. "I wish I owned an NFL team right now. I'd sign him today."
"I don't think anybody in the organization saw this coming," James said of Irving's trade request. "It was definitely a shock.
"I was ready to give him the keys. I tried to help him be as good as he could be. ... I don't have any advice for him now, you're either with us or against us."
James said his previously stated intentions to finish his career with the Cavaliers haven't changed, but he would make a decision on his future after this season.
"It hasn't changed," said James, nodding when asked if he intended to finish his career in Cleveland. "Anytime I'm able to be free agent or my contract ends, I'll approach that when the summer comes."
The 32-year-old James has a player's option for next season worth $35.6 million. Rumors have swirled all summer about James possibly considering the Los Angeles Lakers next season.