ILYA SOMIN: Are there limits to executive discretion in enforcing federal law? “Executive discretion has grown dangerously broad – not because of Obama’s most recent action, but because the enormously broad scope of federal law creates a situation where almost everyone has violated the law at some point, and only a small fraction of offenders can be prosecuted. The president thereby inevitably has broad discretion in deciding which ones to go after.”

Big government is arbitrary government.

Related: The constitutional limits of prosecutorial discretion.