The armed forces were officially integrated in 1948, but racial violence flared as recently as 1972. Race education intensified. Now discriminatory actions–if not always attitudes– are rare.

Illegal drugs plagued the military in Vietnam. In 1981, when 14 people died in a plane crash aboard the USS Nimitz, substance abuse was again blamed. Since then, a zero-tolerance drug policy has been strictly enforced.

Tension came with more women in uniform, from 2 percent of troops to 11 percent in 20 years. Tailhook prompted more navy education, but the jury’s still out.

National debate, spurred by a Clinton campaign promise, forced partial acceptance of gays in the forces. But with no pressure from the brass and a lack of consensus in society, no training is planned.