Why are we not talking about extremist politics in the U.S.?

Ask any of us who works in national security what to do about ISIS, and we’d have no problem pitching you ideas. Even if we lack expertise in the topic or don’t work directly on it, we’d still have opinions and thoughts, because we’ve been swimming in a sea of articles, op-eds, books, hearings, programs, and overall research and debate for years. But ask us about right-wing extremism, a violent ideology that’s killed more Americans than ISIS in the last decade, and most of us would pause — either because we were unaware of the problem or, worse, we were afraid to speak openly about it.