President Joe Biden heralded the next generation of Air Force and Space Force officers Thursday morning with a commencement speech warning of the challenges they face and the responsibility that now rests on their shoulders. Biden spoke for about 30 minutes at the Air Force Academy graduation before donning a blue Air Force cap and congratulating the nearly 1,000 graduates as they crossed the stage for their diplomas. “As you leave these mountains, where the air is rare, you’ll take with you the confidence that your years here have prepared you for whatever is ahead,” Biden said.