a small and very misguided group
Embarrassing, yes indeed, but I would bet that an equally small and misguided group of far left zealots are equally embarrassing to the liberals.
Publicly denouncing? Well, we know that neither side does much of this within their own ranks. On the creationism issue, the best we see from the right is support of teaching both creationism and evolution
Environmental luddites that oppose all things nuclear and space exploration in general could well be denounced and I will gladly applaud any liberal that does so.