US Army Secretary Dan Driscoll has resigned after around 18 months in the post, following months of reported friction with Defence Secretary Pete Hegseth. Driscoll, the youngest-ever army secretary, was widely known as President Trump's "drone guy" for his focus on emerging battlefield technology, and his exit marks the latest in a series of high-profile departures from senior US military leadership under Hegseth's tenure at the Pentagon.

The White House praised the 41-year-old's "outstanding leadership" and effectiveness in advancing Trump's agenda, though the exact cause of the rift with Hegseth remains unclear; reports note Driscoll is close friends with Army Chief of Staff Randy George, who was reportedly also pushed to resign by Hegseth. A former Army officer who served in Iraq in 2009, Driscoll went on to play a leading role in Russia-Ukraine peace talks, took charge of National Guard deployments to US cities, and briefly served as acting head of the ATF. His departure follows those of Navy Secretary John Phelan and several other senior officers dismissed or forced out since Hegseth took over the Pentagon.