After Derrick Rose debuted the shirt, James and several teammates wore shirts protesting the decision not to indict the police officer who placed Eric Garner in a fatal chokehold in July. Garner said "I can't breathe" before he died.
Obama referenced past examples of athletes using their fame to bring change.
"You know, I think LeBron did the right thing," Obama told PEOPLE two days after that Cavaliers-Nets game.
"We forget the role that Muhammad Ali, Arthur Ashe and Bill Russell played in raising consciousness," the president continued.
"We went through a long stretch there where [with] well-paid athletes the notion was: just be quiet and get your endorsements and don't make waves," he also said. "LeBron is an example of a young man who has, in his own way and in a respectful way, tried to say, 'I'm part of this society, too' and focus attention.
"I'd like to see more athletes do that," he added. "Not just around this issue, but around a range of issues."
There have been a series of protests by athletes in recent weeks. Five St. Louis Rams players took the field with a "Hands Up, Don't Shoot" pose protesting a grand jury's decision not to indict police officer Darren Wilson in the shooting death of 18-year-old Michael Brown.
Cleveland Browns wide receiver Andrew Hawkins wore a shirt reading "Justice for Tamir Rice and John Crawford" last Sunday. The 12-year-old Rice was shot and killed last month by police who mistook his air gun for a real firearm. Crawford died in August after police shot him in an Ohio Wal-Mart while he was holding an air rifle.
- Paul Palladino