Acting SECDEF is a retired Green Beret

When President Donald Trump fired former Defense Secretary Mark Esper on Monday, he chose to replace him with someone from outside the Pentagon, rather than elevate Esper’s deputy to the acting SECDEF role. He chose Chris Miller, a retired Special Forces colonel who had been serving as the National Counterterrorism Center’s director. His resume includes a stint as the assistant defense secretary for special operations/low intensity conflict, as well as a battalion command back at 5th Special Forces Group, during the early days of the war in Afghanistan.

Miller became the director of the National Counterterrorism Center in August following a bipartisan confirmation vote in the Senate, a vote Trump touted when naming him as the acting head of the Pentagon, bypassing the deputy secretary of defense who would normally take over on an acting capacity should the defense secretary be fired.

Prior to leaving the NCTC, Miller was working at the Pentagon as the deputy assistant secretary of defense for special operations and combating terrorism.

Before his most recent tour at the Pentagon, Miller was working in the Trump White House, serving from 2018-2019 as the as the special assistant to the President and senior director for counterterrorism and transnational threats at the National Security Council.

Officials say Miller was a driving force in some of the President's anti-Iran and anti-Hezbollah policies, as well as counterterrorism efforts linked to the wars in Syria and Iraq. Prior to going to the White House, Miller served in the Army for 27 years, first as an enlisted soldier and later commissioned as a Special Forces officer, deploying to Afghanistan and Iraq during the earliest days of the US military interventions in both countries.