THE DIFFERENCE BETWEEN NONCOOPERATION AND OBSTRUCTION: When State Resistance Meets the Constitution. “When obstruction occurs, the Constitution does not leave the federal government helpless. The executive branch possesses a sequenced set of lawful responses, ranging from judicial and criminal to, in extreme cases, military, to restore the execution of federal law. Federal courts may enjoin state interference. Conspiracies to obstruct federal officers are illegal under federal criminal statutes. The National Guard may be federalized when governors misuse it to defeat federal authority. And where organized resistance renders ordinary enforcement impracticable, the Insurrection Act authorizes decisive action to reestablish the rule of law. Much has been made of so-called ‘norms’ against the domestic use of military force. Norms may guide discretion, but they do not override law.”

It’s also a norm that states don’t wage war against the federal government.