Forms of argument
From Crooked Timber:
At least three people on the Right, including the most popular political/ current events blogger in the world, suggest that it is legitimate to criticize rich people for not giving money to specific charities (tsunami relief), and that it is especially legitimate if the person being reprimanded has given money philanthropically in the past and made their money via (horrors!) capitalist markets. Given the right's normal antipathy to redistributive policies and affection for the market, this is an odd criticism, though it is logically possible to believe that it's a moral failing not to give money to certain causes and yet it would also be immoral to force donation to those causes. Also, I have not looked into these three individuals personal beliefs, so it is possible that they are supporters of redistribution, since neither the right nor the left are ideologically monolithic. Or these people could just be hacks who want to make it sound like they've uncovered negative information about George Soros when the only fact of the matter is that Soros has not given an interview or press release announcing that he donated money to tsunami relief.
On a separate manner, while I wouldn't think that it is a legitimate criticism of someone's true statements that they have failed to make other true statements about totally unrelated topics, this is one of the most common argumentative tactics seen on blogs of all stripes. Therefore, I might talk later today about an indictment that has been issued in relation to a Clinton fundraiser. I think once I mention an ethical failing by a Democrat, I'm permitted to discuss torture being bad. If I were to say something negative about torture otherwise, I'm obviously just being partisan and wouldn't object to torture if it wasn't for my irrational hatred of Bush. At least I think those are the rules.