I don't see anyone here denouncing Nathan Newman personally, or making ad hominem attacks against him, even though he is a centrist/center-left/liberal or what have you, and for this list is relatively on the far right of it. One reason for that is he is almost always pleasant and good-mannered.
The liberal Michael Lewis followed the various Republican presidential candidates around in 1996, and found Patrick Buchanan relatively one of the more personable, good-humoured and honest candidates. And in fact, Buchanan rarely engages in ad hominem attacks against others, and when then usually in a joking manner. On the other hand, former leftists like David Horowitz, the Dissent and Commentary crowd (or as Woody Allen called them, the Dissentery crowd), drink-soaked popinjay Snitch and so forth do almost nothing but make ad hominem attacks on leftists. I mean, Norman Podhoretz named his book "Ex-Friends".
Despite what MP said, I don't view the loss of these people as a "loss for the left". Snitch is a great example. Talk about trying to bring the masses to your side - you're not going to win over the people in this country, the majority of whom are of Irish (or German, according to the census) heritage, with some boozy Brit with an upper-class accent who writes books trashing Mother Teresa. Good riddance to him.
As far as the crowd who are or have been on this list, Leo Casey was always annoying. MP usually was more convoluted than annoying, and sometimes his arcane memory of far-left sects was a contribution to say the 'spotters list. But for some reason he has been purposefully trying to push peoples buttons on this and other lists over the past few weeks. I don't I myself or others are thin-skinned enough to become upset about something MP or someone would say about ourselves. But I find him making fun of Palestinians, driven out of desperation into strapping a suicide belt on and walking up to IDF checkpoints within Palestine, I find these "punk toilet denunciations" as yous may put it. The disgusting thing about it is he is not attacking some arm-chair middle class leftist in the US, but some poor third-world person, driven to suicide by desperation due to the billions a year in military aid MP's government sends to Israel. At least Snitch usually sticks to attacking the Galloways, the New York Times and what have you.