Dylann Roof is a terrorist.

Before he reportedly confessed to murdering nine people in a Charleston, S.C., church, Roof allegedly said, “You rape our women and you’re taking over our country. And you have to go,” According to CNN, law enforcement sources said the 21-year-old high-school drop out wanted to start a race war. Interviews with Roof’s friends revealed the depth of the racist hatred.

Roof chose Emanuel African Methodist Episcopal Church “because it was a black church.”  Roof believed “the races should be segregated, that whites should be with whites.” And one of Roof’s friends told the New York Daily News that Roof joked about “killing ‘a bunch of people on Wednesday. He flat out told us he was going to do this stuff.’”

The race-fueled carnage in Charleston should come as no surprise to anyone. It happened in a state where the Civil War started. It happened in a state where the treasonous Confederate battle flag still flies, affixed to a pole at a war memorial near the state capitol dome in Columbia, S.C., and cannot be removed without the express consent of each branch of South Carolina’s General Assembly. It was carried out by a man who sported the stars and bars on his license plate and the flags of long-gone racist regimes in South Africa and Rhodesia.

That Roof unleashed hell at “Mother Emanuel” should not come as a surprise, either. The Department of Homeland Security warned us about men like him six years ago. “[W]hite supremacist lone wolves pose the most significant domestic terrorist threat because of their low profile and autonomy—separate from any formalized group—which hampers warning efforts,” the agency warned in an April 2009 entitled “Right Extremism: Current Economic and Political Climate Fueling Resurgence in Radicalization and Recruitment.”

What also hampers warning efforts are friends who remain silent in the face of such hate. The ones who slough off racist talk and musings of mass murder. The ones who do nothing even though the person spewing hate also has a gun. “I feel we could have done something and prevented this whole thing,” one of Roof’s friends said in the New York Times.

Yes, they could have and I hope it haunts them for the rest of their lives.

Follow Jonathan on Twitter: @Capehartj