BALTIMORE — The national debate about anthem protests, patriotism and unity revolving around the NFL and its players was back on vivid display here Sunday at M&T Bank Stadium.

Baltimore Ravens players took a knee before the national anthem, to a mixture of boos and cheers from those in the crowd, then stood for the playing of the anthem before their game against the Pittsburgh Steelers.

An announcement to the crowd asked fans to join the Ravens players and organization in prayer to embrace “kindness, unity, equality and justice for all Americans.”

Steelers players stood on their sideline for the anthem, one week after declining to be on the field for the anthem before their game in Chicago. That thrust the Steelers into the controversy, amplified by President Trump, about NFL players’ national anthem protests, even as the Steelers called their action nonpolitical. Steelers offensive tackle Alejandro Villanueva, a former Army Ranger, broke ranks with his teammates and stood at the front of a tunnel leading to the field, with his hand over his heart, for the anthem in Chicago. He later said he regretted isolating himself from his teammates.

No Ravens or Steelers players were kneeling during the anthem Sunday.

Fans in the stands could be spotted wearing red, white and blue shirts and hats. A few waved American flags. One fan stood along the railing by the field during pregame warm-ups and held a sign, apparently directed at protesting players, saying: “Europe Accepts Immigrants.” Fans cheered the playing of, “God Bless the U.S.A.” about 15 minutes before kickoff, then began a brief chant of, “U.S.A.! U.S.A.!”

The anthem was performed by a vocal trio from the United States Air Force Heritage of America Band after the Ravens’ previous anthem singer resigned.

Earlier Sunday, fans gathered around the Ray Lewis statue outside the stadium, taking photos as security staff looked on. One man, Tom Rose of White Marsh, Md., wore an American flag shirt and a stars-and-stripes cap with “USA” written on it. Underneath his flag shirt was a Ravens jersey.

For the second consecutive Sunday, several NFL players took a knee during the national anthem or raised their fist. (The Washington Post)

“Flag and country first. Football second,” said Rose, adding that he is a Baltimore County police officer. “I’m here. I have season tickets. I called the Ravens and I asked them. I said, ‘Is anybody gonna take a knee this week?’ They said they’re not announcing what the Ravens are doing. I said, ‘Well, this will be the last game I go to if someone takes a knee.’ I’m gonna wear my flag stuff, show my support for the country, support for the flag. I do have my Ravens jersey on, in case no one does.”

Rose said he has family members who are in the military and who are fellow police officers. He’s “all right” if players want to protest, he said, but they should “get in their Hummers, get in their Bentleys” and do it elsewhere.

“They don’t have to do it here in front of the flag,” Rose said. “It’s just the wrong place to do it. . . . There’s five people in our section in my row that we have tickets together, my family. Two of them didn’t come today. And the tickets are going to waste. They didn’t want somebody else to have it. They wanted that seat to be empty. I respect that.”

Baltimore became a bit of an epicenter of the debate. It’s a city with a recent history of racial unrest, and Ravens players helped to set a tone for the previous Sunday’s leaguewide reaction to Trump’s comments two days earlier at a political rally in Alabama. Trump said that any player who protests during the national anthem should be fired; he called such a player a “son of a bitch.”

Lewis, the former standout linebacker for the Ravens, went to both knees during the national anthem  before the team’s game against the Jacksonville Jaguars in London the previous Sunday, which began at 9:30 a.m. ET. Lewis was joined by more than a dozen current Ravens players. In response, a petition was started calling for the removal of Lewis’s statue outside M&T Bank Stadium.

“I know it’s not coming down,” Rose said Sunday by the statue. “I think that’s a stretch. I know Ray is passionate. I just wish he’d put it in the right area. I mean, going to London on foreign ground and getting down on both knees, the optics are bad. And I don’t even know what the protest is for, for most of the players, because they don’t say what it’s for. I never heard [Terrell] Suggs come out and say why he did it or C.J. Mosley or Mike Wallace. What are they doing it for?

“They should communicate what they’re doing it for. And they keep saying it’s no disrespect to the flag or the military. But it is. . . . It’s disrespectful to the men and women that serve this country, the officers, the military. It’s a minute thirty [seconds]. Stand up for a minute thirty and then why don’t they do a protest like three minutes into the third quarter? . . . You don’t need to do it for the flag.”

But others said they support the players’ right to protest.

Luis Carreno said he is a Ravens fan from Phoenix. He was dressed in a Lewis jersey taking a selfie by the statue.

“I don’t really care for it,” he said. “I don’t pay attention to politics at all. I don’t even vote. I don’t really care for the politics about it. I’m kind of annoyed that they did bring it into football and made it a part of it. But at the end of the day, I’m just here for a game. This is my escape from all that’s out here, 60 minutes of great football. That’s all I care for. So as far as them kneeling and all that, I’m not gonna do it. But I respect everybody else’s decision to do whatever they want to do as Americans. Land of the free, home of the brave, so do what you want. It doesn’t bother me.”

A few minutes before kickoff, Art Cox stood on the fuel dock of the Hard Yacht Cafe, his waterfront restaurant in working-class Dundalk, Md., and watched the military jets getting into formation overhead for their flyover during the anthem at M&T Bank Stadium just a few miles away.

“It’s pretty quiet in there,” Cox said, gesturing toward the restaurant.

Normally, he said, the restaurant would be packed for a Ravens game, the parking lot would be jammed and boats would be lining up for slips.

But on this Sunday, half the tables sat empty and only a few customers sat at the bar. The TVs were tuned to the game, but the volume was turned off and a band was setting up to play outside.

When one man asked the bartender to turn up the volume, she said she couldn’t, and the man canceled his food order and left.

After last Sunday’s kneel-down in London, more than a dozen of Cox’s customers walked out, and the ones who remained were almost unanimous in their disgust over the players’ protest.

Cox spent much of the week pulling all the Ravens decorations and advertising signage off the walls, even pulling in a purple, Ravens-logoed buoy that sat just off the dock. He decided to stop building the restaurant’s fall Sundays around the Ravens, and hired the band to play at 1 p.m.

“We’ll have to see how it goes,” Cox said of his business on Sunday. “But so far it’s not looking good.”

Some people at the restaurant wore Ravens jerseys and watched the game attentively — with no volume — but most barely even noticed it was on.

Trump is not letting the issue go. He wrote Saturday on Twitter: “Very important that NFL players STAND tomorrow, and always, for the playing of our National Anthem. Respect our Flag and our Country!”

NFL Commissioner Roger Goodell sent a memo to league staff members in New York, New Jersey, Los Angeles and overseas at Sunday’s Dolphins-Saints game in London.

“This past week was a challenging week for all of us, but I am proud of the way our clubs and players have come together and entered into [dialogue] like never before,” Goodell wrote. “On Friday, the Broncos released a statement directly from their players. I wanted to share it with you as it provides a narrative of this past week and their hopes for today.”

The statement by Broncos players forwarded by Goodell to the NFL staffers read in part: “Make no mistake — our actions were in no way a protest of the military, the flag or those who keep us safe. We have nothing but the deepest love and respect for those who protect our way of life and the freedoms we enjoy as Americans.

“While there’s no greater country, it’s not perfect. Inequalities still exist, and we have work to do in ALL forms of social justice. We can all do better …. We’re a team and we stand together — no matter how divisive some comments and issues can be, nothing should ever get in the way of that. Starting Sunday, we’ll be standing together.”

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