Story highlights Fifty-three organizations list reasons why they believe Michael Flynn should not serve in this role

The National Security Adviser position does not require Senate confirmation

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Washington (CNN) Progressive organizations including MoveOn.org and J Street signed a letter with another 51 other nonprofit groups asking that President-elect Donald Trump dump Retired Lt. General Michael Flynn as his national security adviser.

"While deserving respect for the time he has served our country in uniform, we feel General Flynn is unfit for serving in this critical post," the organizations wrote in a statement. "His appointment will damage America's standing in the world and pose a threat to our national security."

Trump's transition team did not immediately respond to a request for comment by CNN.

In the letter, the organizations list several reasons why they believe Flynn should not serve in this role, which does not require Senate confirmation, including mentioning past Islamaphobic statements he's made and for peddling anti-Muslim conspiracy theories.

"He has written that 'fear of Muslims is rational' and said that 'Islam is a political ideology' and 'a cancer' that 'hides behind being a religion,' and continuously peddles the nonsensical fear of 'Shariah law' spreading in the United States," the letter said.

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