“You’ve got to have people who are technically competent,” said retired Army Maj. Gen. Stephen V. Reeves, who served as an intelligence officer in Western Europe.

The SA-11 is a 1972-era weapon system, and is not as technologically advanced or easy to operate as more modern weaponry.

“This is a hard system to use, in today’s terms,” said retired Army Lt. Gen. Patrick J. O’Reilly, a former director of the U.S. Missile Defense Agency, who estimated that each of the SA-11 crew members would have needed at least six months of training.

“You don’t just take some folks off the street, and 30 days later they’re trained,” he said.