When I arrived in my first infantry unit in 2000, I remember encountering non-commissioned officers who were by then quite adept at interpreting the tattoos on the young white men arriving to the unit fresh from basic infantry training. By that point, though, recruiters were already weeding out most of the men who showed up with any sign of affiliations with white supremacist groups.

By the time I arrived at the elite 75th Ranger Regiment in 2002, meanwhile, the command sergeant major—the senior enlisted man in the regiment—was black, a regimental first. He had the respect of the entire regiment for two reasons: his rank, naturally, but also the toughness he displayed while rising through the ranks at a time when, in the 1980s, African-Americans were decidedly unwelcome in certain quarters of the special operations community.