Washington, D.C., is an actual swamp riddled with proverbial diseases, which are spread by consultants, lobbyists, and other parasites on the body politic. An effective statesman — especially a president — must enter the swamp with an immunity to these viruses, or he will fall victim to them.

Scott Walker’s actions suggests he lacks the required immunity to special-interest pleading. The $80 million state subsidy he approved this week for the Milwaukee Bucks is the latest evidence.