Tom Cotton asked Gen. Milley why he did not resign despite President Biden disregarding his advice.
Milley said "it would be an incredible act of political defiance" to resign, defending civilian military control.
"Just from a personal standpoint, my dad didn't get a choice to resign at Iwo Jima," Milley also said.
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During his testimony before the Senate Armed Services Committee on Tuesday, Chairman of the Joint Chiefs of Staff Gen. Mark Milley defended his decision not to resign in the wake of the US withdrawal from Afghanistan despite President Biden reportedly differing from his desire to stay in the country for longer.
"I can only conclude that your advice about staying in Afghanistan was rejected, I'm shocked to learn that your advice wasn't sought until August 25th on staying past the August 31 deadline," Republican Sen. Tom Cotton of Arkansas said to Milley. "I understand that you're the principal military advisor, that you advise, you don't decide, the President decides. But if all this is true, General Milley, why haven't you resigned?"
In responding, Milley drew both on principles of civilian control of the military as well as his own sense of personal honor.
"As a senior military officer, resigning is a really serious thing. It's a political act if I'm resigning in protest," Milley began. "My statutory responsibility is to provide legal advice, or at best military advice to the president, and that's my legal requirement. That's what the law is."
"The President doesn't have to agree with that advice, he doesn't have to make those decisions just because we're generals, and it would be an incredible act of political defiance for a commissioned officer to just resign because my advice is not taken," Milley continued. "This country doesn't want generals figuring out what orders we're going to accept and do or not. That's not our job. The principle of civilian control of the military is absolute, it's critical to this republic."
"In addition to that, just from a personal standpoint, my dad didn't get a choice to resign at Iwo Jima," he said, referring to his father Alexander Milley, a Marine who fought in WWII.
"And those kids there at Abbey Gate, they don't get a choice to resign, and I'm not going to turn my back on them," Milley said in an apparent reference to the 13 US service members killed by an ISIS-K attack at the Kabul airport. "I'm not gonna resign- they can't resign, so I'm not going to resign, there's no way."
He added, "if the orders are illegal, we're in a different place, but if the orders are legal, from civilian authority, I intend to carry them out."