SAN FRANCISCO (CBSNewYork/AP) — From the White House to San Francisco police union headquarters to NASCAR drivers and the Veterans of Foreign Wars, Colin Kaepernick’s name came up Monday as his decision to sit down during the national anthem reached far beyond football.

And many aren’t thrilled with the 49ers quarterback’s strong words about why he is doing it: To instigate change and challenge authority when it comes to race relations and what he considers police brutality.

“I’m sorry but (at)Kaepernick7 needs to learn the fact about police before running his dumbass mouth! He has no clue what they go thru! (hashtag)idiot,” Tony Stewart tweeted.

Even his former coach, outspoken Michigan leader Jim Harbaugh, chimed in from afar in disagreement with Kaepernick’s tactics — clarifying some earlier remarks that questioned the quarterback’s motivation.

“I apologize for misspeaking my true sentiments. To clarify, I support Colin’s motivation. It’s his method of action that I take exception to,” Harbaugh posted on Twitter.

Kaepernick, who has sat through the anthem at all three 49ers preseason games so far, is prepared to keep fighting for what he believes in, even alone, CBS2’s Otis Livingston reported.

“The fact that it has blown up like this, I think it’s a good thing. It brings awareness,” Kaepernick said Sunday. “Now, I think people are really talking about it. Having conversations about how to make change. What’s really going on in this country. And we can move forward. …There is police brutality. People of color have been targeted by police. So that’s a large part of it and they’re government officials. They are put in place by the government. So that’s something that this country has to change. There’s things we can do to hold them more accountable. Make those standards higher.”

Martin Halloran, the San Francisco Police Officers Association president, sent a letter Monday to NFL Commissioner Roger Goodell and 49ers CEO Jed York denouncing Kaepernick’s “ill-advised” statements and a “naïveté” and “total lack of sensitivity” toward police, along with an “incredible lack of knowledge” about officer-involved shootings.

The police union invited Kaepernick or anyone else from the league to visit the San Francisco police academy to build communication and understanding about the profession.

“I only wish Mr. Kaepernick could see the emotional and psychological challenges that our officers face following a fatal encounter,” Halloran wrote. “Some are so affected they never return to the streets. In short, Mr. Kaepernick has embarrassed himself, the 49er organization, and the NFL based on a false narrative and misinformation that lacks any factual basis.”

White House spokesman Josh Earnest said he was confident President Barack Obama is aware of Kaepernick’s actions but hadn’t spoken directly with the president about it.

“In general, what I can say is that I certainly don’t share the views that Mr. Kaepernick expressed after the game in explaining his reasoning for his actions, but we surely would all acknowledge and even defend his right to express those views in the settings that he chooses,” Earnest said. “That’s what he’s done, and even as objectionable as we find his perspective, he certainly is entitled to express it.”

Kaepernick’s stance about sitting through the anthem, which he further explained Sunday after he was shown sitting on the bench for “The Star-Spangled Banner” before Friday’s preseason loss to the Packers, was still the chatter around the NFL, too.

Steelers left tackle Alejandro Villanueva, who played at Army and served in Afghanistan before forging a job in the NFL, said he agrees that the U.S. “is not perfect” but insists it is the best country and he is unsure how he would react if one of his teammates sat down for the anthem.

“I just know that I am very thankful to be an American. I will stand very proudly, and I will sing every single line in the national anthem every single time I hear it,” Villanueva said. “I will stop whatever I am doing, because I recognize that I have to be very thankful to be in this country.”

New York Giants head coach Ben McAdoo said he would be disappointed if one of his players decided to to stand during the anthem.

“The way we operate for the national anthem, we consider it a small gesture to those who served and sacrificed their lives for our country and for us to play and coach in this great game,” McAdoo said. “I’d be disappointed if one of our guys chose not to stand. It’s their choice, it’s not mandatory, but we feel it’s important.”

Philadelphia Eagles rookie linebacker Myke Tavarres initially said Monday he would sit during the national anthem for Thursday’s game against the New York Jets, but later reversed course and now will stand.

New Yorkers CBS2 spoke to also criticized Kaepernick.

“By not standing for the national anthem, every soldier that is defending our country, you’re disrespecting them” one man said.

Another said, “I think he is a disgrace. He’s not a very good citizen, is he? Get rid of him.”

As some of Kaepernick’s teammates noted Sunday, many are offended by his bold move — one he plans to continue indefinitely.

“The American flag and our national anthem stand for something, and the Veterans of Foreign Wars of the United States salutes all who stand with us,” said Veterans of Foreign Wars National Commander Brian Duffy.

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