As if having most of Hollywood lambast President Trump for his Twitter attacks on the mayor of San Juan over the Puerto Rican crisis weren't enough, now the former head of the CIA is questioning whether the president is a leader capable of supporting free speech and safeguarding American lives.

In an oblique statement issued Saturday via a tweet, former CIA chief John Brennan suggested that by focusing on whether football players stand or kneel during the national anthem rather than the catastrophic problems in Puerto Rico, President Trump is demonstrating he does not have the leadership qualities the American people need.

Brennan does not directly refer to the president in the portion of his statement that's about the NFL issue, but it seems clearly about Trump's ongoing tweets expressing outrage over NFL players not standing during the national anthem to protest racial inequality in the United States.

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Nick Shapiro, formerly one of Brennan's senior advisers, tweeted out Brennan's statement Saturday night. Brennan himself does not have a Twitter account.

In the statement, Brennan said that taking a knee during the national anthem shows respect for the flag while at the same time expressing concern about problems within American society that need to be addressed.

"Pejorative and caustic comments about the practice show a disregard for one of the most important foundational principles of our great Nation — freedom of expression," he wrote.

It also shows an ignorance of the corrosive effects of racism and class bias in our country, he wrote.

Brennan was head of the CIA during the Obama administration from March 2013 to January 2017.

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"It is at times like this that government officials demonstrate that they either have or sorely lack the leadership qualities and values that are needed and expected by the American people," his statement went on to say.

Brennan then writes that the primary responsibility of the president is "to do anything possible to safeguard the lives of American citizens," which is why he should have a "laser-like focus on mitigating the catastrophic damage of Hurricane Maria on the people of Puerto Rico."

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Saturday morning, Trump went on a Twitter rampage against the mayor of the capital city of Puerto Rico, San Juan. He accused her of poor leadership and said Democrats had told her to be "nasty" to him.

At the beginning of the month, Brennan was named a distinguished fellow for global security at the Fordham University School of Law’s Center on National Security.

Follow Elizabeth Weise on Twitter: @eweise