Walker seems torn between the federalism that Republicans traditionally support (in theory, at least) and their criticism of President Obama’s lawless ways. The result is barely coherent. Although it’s true that Obama has been known to ignore the law when it’s inconvenient (as have his predecessors from both parties), his response to marijuana legalization is not a good example of that tendency. The Justice Department, for good and ill, has a great deal of discretion in enforcing the Controlled Substances Act. Its current policy of focusing on marijuana offenders who violate state law or impinge on “federal enforcement priorities” uses that discretion in a way that respects state policy choices, which is something federalists should welcome.

According to the Supreme Court’s 2005 ruling in Gonzales v. Raich, the power to regulate interstate commerce authorizes the federal government to enforce its ban on marijuana even in states that have legalized the drug for medical or recreational use (indeed, even against people whose marijuana-related activities are confined to their homes). The Court’s absurdly broad reading of the Commerce Clause should trouble federalists. “If Congress can regulate this under the Commerce Clause,” dissenting Justice Clarence Thomas observed in Raich, “then it can regulate virtually anything—and the Federal Government is no longer one of limited and enumerated powers.” But even if we assume that the feds constitutionally can arrest state-licensed marijuana merchants, that does not mean they should, especially if you believe, as Walker says he does, that it “should be a state issue.”