Block on Trump's Asylum Ban Upheld by Supreme Court
They're right there in the Constitution, prefacing the right to bear arms: "A well regulated Militia, being necessary to the security of a free State ..." Those words were ratified in 1791, a time before a standing army, National Guard, or city, county, or state police forces.
Are militias still necessary? And beyond that, are they even legal?
The legality of militias depends largely on which militia you're talking about. By strict definition, a militia is a group of private citizens who are trained for military duty in case they need to be called upon to defend their state or country in an emergency. And as the United States has grown and changed, so has the definition and sanctioning of militias.
Some states have a reserve military or state-sanctioned militia, referred to as the state guard or foot guard. For example, the New York Guard is a volunteer force that provides additional manpower and support to the New York National Guard. On the other hand, Texas considers any male citizen between the ages of 17 and 45 as belonging to the "Unorganized Reserve Militia" and the state constitution gives the county sheriff and the governor the authority to call on the unorganized reserve militia to uphold the peace, repel invasion, and suppress rebellion.
While such state-sanctioned militias have been utilized in the past, the current, common definition of militia refers mostly to far-right paramilitary groups who see themselves as opposing a tyrannical government. In this sense, any group of private citizens with military-style weaponry and training can self-apply the term militia.
Such groups, in and of themselves, are not illegal. But they become the target of law enforcement for engaging in other illegal activity like firearms violations, tax evasion, or threats of violence. The Southern Poverty Law Center estimates there are 276 antigovernment militias nationwide, and while mere membership in a militia may not be illegal, some actions (like an armed takeover of a federal building) may be.
If you're wondering if your militia is illegal, you might want to consult state law or an experienced criminal defense attorney about your rights.