They have been classified as a hate group - by the Southern Poverty Law Center.
There was some controversy over the SPLC in the past couple of years, I can't recall quite why, but I suspect that they are another organisation like Stonewall; with a strong reputation of anti-discrimination, pissed away by their recent heads chasing the funding.
It's the problem with US organisations, we're not totally familiar with them or their reputation. It's often hard to know who are to be trusted.