From Green Berets to the S-1 clerk and everyone in between, every soldier has something in common with each other: they’ve all started their military careers at the U.S. Army’s Basic Combat Training.

VIRGINIA BEACH, Va. — More than 40 feet up the tower at Fort Jackson, Army recruit Robert Smith missed setting his feet on the 4-by-4 plank from which he was to start rappelling down. “I said: ...

Airman Basic Matthew Deffer kept a brisk pace on his pushups until the 25th repetition, when he started taking an extra couple of seconds to recover. At the 30th pushup, he began to show his age — 41.