EXPLAINED: What is National Guard? Why are they in Los Angeles and why Trump’s use of it is sparking backlash?

Around 4,000 troops were deployed to the streets of Los Angeles on Sunday amid ongoing protests against President Donald Trump’s immigration policies. The soldiers belong to the California National Guard and were sent under Trump’s orders, a move opposed by California Governor Gavin Newsom.

Newsom criticised the decision, calling it “immoral” and “unconstitutional.” He announced plans to take legal action against the Trump administration for federalising the state’s National Guard without his consent.

“We didn’t have a problem until Trump got involved,” Newsom wrote on X (formerly Twitter), alongside a letter he addressed to Defence Secretary Pete Hegseth, urging him to cancel the federal order.

What is the National Guard?

The National Guard is a reserve wing of the US military, which can be activated by state governors or the president to handle domestic emergencies such as natural disasters, civil unrest or even military missions abroad. In rare instances, US presidents have federalised the National Guard to intervene in domestic protests, as is happening now in Los Angeles.

Guard members typically live and work in their communities, serving part-time while holding civilian jobs or attending school. The force is divided into two main branches: the Army National Guard and the Air National Guard. Together, they serve as reserve units for the main branches of the military.

Guard’s role in war and humanitarian missions

The National Guard has played a significant role in both war and peace. During the height of the Iraq conflict in 2005, Guard troops made up over half of all US combat brigades in the region. More recently, they’ve helped train and support Ukraine’s military.

All recruits undergo basic military training and are required to attend regular drills one weekend a month, plus a longer training session each year.

A history rooted in early America

The origins of the National Guard date back to 1636, when the Massachusetts Bay Colony formed its own militia. These state-based militias were vital during the Revolutionary War and continued to exist even after the US formed its first national army in 1775.

Today, Guard units are only called up when necessary, during natural disasters, foreign missions, or periods of domestic unrest. Both governors and the president have the authority to activate the Guard.

A rare move by the president

It is extremely uncommon for a US president to federalise a state’s National Guard without the governor’s consent. The last such action was in 1965, when President Lyndon B. Johnson sent the Alabama National Guard to protect civil rights marchers in Selma.

Trump cited an old law that allows the president to act in cases of “rebellion or danger of rebellion against the authority of the Government of the United States.” Governor Newsom described this action as a “serious breach of state sovereignty” and requested the orderbereversed.