On Dec. 20, Trump initially tweeted that Mattis had retired. That evening, the Pentagon gave reporters copies of Mattis' resignation letter, which made clear the retired Marine general could no longer serve under Trump, citing irreconcilable differences.
"I wasn't happy with Mattis," Trump said. "I told Mattis to give me a letter. He didn't just give me that letter. I told him."
In his resignation letter, Mattis wrote the United States needs to be "resolute and unambiguous" towards adversaries such as Russia and China while showing respect to allies.
"Because you have the right to have a Secretary of Defense whose views are better aligned with yours on these and other subjects, I believe it is right for me to step down from my position," Mattis wrote.
Trump told the New York Times that Mattis' choice of words shows he was ordered to quit.
"That's why in the letter he wrote, 'You have to have your own choice,'" Trump said. "The reason he said that was because I said, 'You're just not my choice.'"
This is the second time the president has claimed that Mattis' departure was not voluntary. At a Jan. 2 cabinet meeting, Trump told reporters that he "essentially fired" Mattis for U.S. military's lack of progress in Afghanistan.
"What's he done for me?" Trump said. "How has he done in Afghanistan? Not too good. Not too good. I'm not happy with what he's done in Afghanistan. And I shouldn't be happy.
"So, I mean, I wish him well. I hope he does well. But as you know, President Obama fired him, and essentially so did I. I want results."
U.S. Cyber Command is reportedly going on offense against Russia's power grid by placing "potentially crippling malware" in its systems, The New York Times reported Saturday.
The cyber incursions, authorized to Cyber Command under new authorities that do not require presidential approval, have gotten more "aggressive" and seem to be a warning that the U.S. can respond to Moscow's past cyberattacks, such as the 2016 incursion into the Democratic National Committee and its attack on Ukraine's power grid.
DUBAI/WASHINGTON (Reuters) - The United States on Friday blamed Iran for attacks on two oil tankers at the entrance to the Gulf and said it was seeking international consensus about the threat to shipping, despite Tehran denying involvement in the explosions at sea.
The Navy has named a female president of the U.S. Naval War College for the first time in its history just days after ousting her predecessor amid allegations of excess spending and inappropriate behavior.