Journalist Soledad O’Brien, the CEO of Starfish Media Group, on Monday took aim at Sen. Marco Rubio (R-FL) after he declined to criticize President Donald Trump for insulting a former Navy SEAL who is responsible for killing terrorist mastermind Osama bin Laden.

In a Sunday interview on Fox News, Trump complained about retired Navy Admiral William H. McRaven, who has called the president a “threat to democracy.” According to Trump, McRaven and his fellow Navy SEALs should have taken out bin Laden “a lot sooner.”

Rubio responded on Monday by praising McRaven — but he declined to condemn Trump’s attack.

“I do know that few Americans have sacrificed or risked more than he has to protect America & the freedoms we enjoy,” Rubio wrote. “I am grateful for his service.”

I don’t know if Adm. William McRaven shares my political views or not.

But I do know that few Americans have sacrificed or risked more than he has to protect America & the freedoms we enjoy.

His military career exemplified honor & excellence.

I am grateful for his service.

— Marco Rubio (@marcorubio) November 19, 2018

O’Brien, a former CNN host, called Rubio’s tweet “absolute cowardice.”

“[Marco Rubio] is such a coward with this response,” she wrote on Twitter. “Does not call out the President of the United States for insulting Adm. McRaven. Rubio is a terrific example of Republican lawmakers terrified of Trump. Absolute cowardice.”

@marcorubio is such a coward with this response. Does not call out the President of the United States for insulting Adm. McRaven. Rubio is a terrific example of Republican lawmakers terrified of Trump. Absolute cowardice. https://t.co/cBnTPt7S1k

— Soledad O’Brien (@soledadobrien) November 19, 2018