Washington is going to have a hard time explaining how the biggest U.S. intelligence leak in a decade may have been committed by a 21-year-old airman whose role — "cyber transport systems journeyman” — required a high-school degree, a driver’s license and up to 18 months of on-the-job-training.

The FBI arrested Jack Teixeira, of Dighton, Massachusetts, on Thursday, with the promise of a swift arraignment on Friday. Attorney General Merrick Garland said he was being held in connection with the "unauthorized removal, retention and transmission of classified national defense information.”

As Pentagon jobs go, Teixeira’s was pretty junior. An Air Force job description says workers like him "keep our communications systems up and running and play an integral role in our continuing success.” He joined the Air National Guard in 2019, according to his service record.