In recent weeks, professional football stadiums have become battlegrounds for a heated culture war centered around "The Star-Spangled Banner."

Goodell said that he "didn't discuss" whether NFL teams would or would not discipline players who continued to kneel. He also said he has not spoken with President Donald Trump about the protests.

Responding to a series of questions about pro football players' protests, Goodell said that while only "about a half a dozen players" continue to kneel for the national anthem, "we're going to continue to work to try to put that at zero."

The NFL believes "everyone should stand for the national anthem," league Commissioner Roger Goodell said at a press conference on Wednesday.

What began with San Francisco 49ers quarterback Colin Kaepernick's refusal in 2016 to stand for the anthem as a protest against racial injustice swept throughout the league in recent weeks.

Players and coaches knelt during the anthem, as much in opposition of President Trump's criticism as in support of political change. Politicians joined the fray, and #TakeAKnee became a trending hashtag on social media.

Trump has accused players who kneel for the anthem of disrespecting the military, and has called for the NFL to censure the protests at rallies and in tweets.

On Wednesday morning, Trump again attacked the NFL over the protests. "The NFL has decided that it will not force players to stand for the playing of our National Anthem," he said. "Total disrespect for our great country!"

Trump tweet

Goodell, while maintaining that players should stand for the anthem, said the NFL is not looking to become a political organization.

"What we're trying to do is stay out of politics," he said.

On the game itself, Goodell was asked about the prevalence of the degenerative brain disease CTE in NFL players. The issue of brain damage now forms the basis of a lawsuit against the league by the family of Aaron Hernandez, a former pro player convicted for murder who ultimately committed suicide in prison.

"I think there's been a great deal of focus on this issue of brain trauma," Goodell said. "We'll let the lawyers handle that and deal with it."