I agree with Mark that there is much that is amusing about Cass Sunstein’s op-ed. I think it’s worth emphasizing, though, that Sunstein expressly states that it was “reasonable” for Roberts to “raise[] questions about the constitutionality of some applications of the Endangered Species Act.” This concession from a leader of the Left should undermine those who have been trying to make the arroyo toad the mascot of their opposition to Roberts. It would also seem to compel the concession that it would be reasonable to raise more general questions about the scope of Congress’s Commerce Clause power.