In an impassioned memo sent three days after San Francisco 49ers quarterback Colin Kaepernick ignited national controversy by refusing to stand for the national anthem before a football game, University of Texas System Chancellor Bill McRaven urged his athletes not to repeat the gesture of protest.

"While no one should be compelled to stand, they should recognize that by sitting in protest to the flag they are disrespecting everyone who sacrificed to make this country what it is today — as imperfect as it might be," he wrote on Aug. 29.

McRaven is a former admiral who is most famous as the architect of the Navy SEAL raid that killed Osama bin Laden. He retired from the military in 2014 and became chancellor in early 2015. In his memo, he described a strong passion for the flag.

"Those that believe the flag represents oppression should remember all the Americans who fought to eliminate bigotry, racism, sexism, imperialism, communism, and terrorism," he wrote.

“ It is a flag for everyone, of every color, of every race, of every creed, and of every orientation, but the privilege of living under this flag does not come without cost. Nor should it come without respect. ” — Bill McRaven, University of Texas System Chancellor

The memo was addressed to the presidents and athletic directors of the eight universities that are members of the UT System, including UT-Austin. It asks the recipients to "encourage your coaching staff and your players to stand up straight when the National Anthem" is played. The coaches and players should "face the flag and place their hand over their heart as a sign of respect to the nation."

McRaven made a similar request in January but expressed a need to reiterate it after the Kaepernick controversy. Still, he acknowledged the right of Americans to protest and didn't say anything about it being mandatory.

"I spent 37 years defending freedom of speech and freedom of expression," he wrote. "Nothing is more important to this democracy. Nothing!"

He then goes on to list American heroes who flew the flag, including buffalo soldiers, suffragists and the Tuskegee Airmen.

"It marched with Martin Luther King, Jr. It rocketed into space on the shoulder patches of women, gays, Hispanic, Asian and African American astronauts. Today, it waves high over the White House. It is a flag for everyone, of every color, of every race, of every creed, and of every orientation, but the privilege of living under this flag does not come without cost. Nor should it come without respect," he wrote.

The memo doesn't specifically mention Kaepernick, who remained seated or took a knee during the anthem for each preseason football game this year. In an interview after the Aug. 26 game when his gesture was first noticed, he said that he was protesting the oppression of black people in America.

"I am not going to stand up to show pride in a flag for a country that oppresses black people and people of color," Kaepernick said, according to NFL.com. "To me, this is bigger than football and it would be selfish on my part to look the other way. There are bodies in the street and people getting paid leave and getting away with murder."

Disclosure: The University of Texas System and the University of Texas at Austin have been financial supporters of The Texas Tribune. A complete list of Tribune donors and sponsors can be viewed here.

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