Ad hominem means against the person, so even if this weren't an example of a fallacy it would be an ad hominem attack. As has been pointed out, people are taki

Ad hominem means against the person, so even if this weren't an example of a fallacy it would be an ad hominem attack. As has been pointed out, people are taking issue with Mao, the person, instead of dealing with his accusations. And that is an example of an ad hominem fallacy. As to merit, fallacies have no bearing on actual truth value, only on soundness of argument. I think that's what you were getting at. For whatever it's worth, I'm no Mao fan.