Critics have blasted George W. Bush’s portraits as “amateur, very literal-minded” and “like a freshman art student attempting alla prima,” but it is not clear how much of this opinion free-for-all draws on in-person experience of the artworks at the Bush Presidential Library in Dallas and how much is based on mediocre photos and rampant ignorance. Certainly, some of the former president’s freshman efforts are not notable, but more are remarkable, and a few outstanding. Bush’s portrait of Vladimir Putin is stunning, fierce and deeply revealing. It exposes its subject’s realities, as successful portraits do. Other paintings show person...