What Is the National Guard, and Who Controls It?

U.S.|What Is the National Guard?

The Trump administration’s effort to send hundreds of National Guard troops into one major American city after another has prompted a multistate court fight.

As the legal battles escalate, here’s what to know about the National Guard.

What is the National Guard?

The National Guard is a state-based military force made up of hundreds of thousands of trained soldiers who typically serve only part-time, but may be activated in times of need, most often during natural disasters, wars or civil unrest.

When they are not on duty, Guard troops typically hold civilian jobs or attend college.

The overall force has two parts, the Army National Guard and the Air National Guard. Each functions as a reserve force for the associated branch of the active-duty military. National Guard troops can be called up and deployed overseas to support military operations abroad, as they were during the Iraq and Afghanistan wars.

The Army National Guard, which descends from colonial and state militias, is the oldest part of the U.S. military.

Who controls the National Guard?

Both state governors and the president have the power to activate National Guard troops. When presidents have done so for duty in the United States, it has almost always been at the request of state or local officials. For example, President George H.W. Bush activated California National Guard troops in 1992 following a request from the governor of California for help quelling riots related to the killing of Rodney King.

When President Trump deployed the California National Guard to the streets of Los Angeles over the summer in response to protests against his immigration crackdown, it was the first time since the civil rights movement in 1965 that a president had summoned a state’s National Guard troops against the will of the state governor.

A federal judge later ruled that the Mr. Trump’s use of the troops to Los Angeles was illegal, saying that the president had effectively turned the troops into a “national police force” in violation of the Posse Comitatus Act, a 19th-century law that generally prohibits the use of federal troops for domestic civilian law enforcement.