The U.S. has the airlift capability to deliver an Army armored brigade combat team to South Korea in 30 days, a task that would take up to 200 flights by C-17 transports, but moving a larger force—especially into a contested environment—would tax available mobilization assets, the commander of U.S. Transportation Command told Congress.

“We do not have the capability that I wish we had, but we have a capability that can provide a force when needed,” Air Force Gen. Darren W. McDew told a Senate committee. McDew, who has headed the command for almost two years, said many airlift and sealift assets are in the commercial sector, making them dependable but not something that would be sent into contested areas.

Moving the Army is a big part of the command’s responsibility, he said.

“When North Korea increased its provocation of our Pacific allies, America responded with assistance. USTRANSCOM delivered that assistance in the form of missile defense systems, personnel and support equipment, moving by sea and air 3,000 miles across the Pacific Ocean,” McDew said. “When you read about America's brigade combat teams rolling through Europe, it was USTRANSCOM's ability to provide a decisive force to reassure European allies. When America needed B-2 stealth bombers to fly 11,000 miles from Missouri to Libya and back, it was our air refuelers that got them.”