By Nick Turse

A defense official, speaking on the condition of anonymity for fear of retribution, called the activation of the Marines a “provocation” designed to foster to a “manufactured crisis.”

Experts question the legality of the mobilization of the Marines.

On Saturday, President Donald Trump took the already extraordinary action of calling up more than 2,000 National Guard troops to tamp down demonstrations in California. In doing so, he exercised rarely used federal powers that bypassed Gov. Gavin Newsom’s authority.

He followed it up two days later with an even more extreme move. While it is unclear under what authority Trump and the Defense Department did so, US Northern Command activated 700 Marines from the 2nd Battalion, 7th Marines, 1st Marine Division, assigned to Twentynine Palms, California.

They are being shipped out to support Task Force 51 -a deployable command post used in crisis response- “who are protecting federal personnel and federal property in the greater Los Angeles area,” according to a statement issued by NORTHCOM.

“The level of escalation is completely unwarranted, uncalled for, and unprecedented -mobilizing the best-in-class branch of the US military against its own citizens,” Newsom’s office said in a statement.

“Military presence is not needed. The state is already working with local partners to surge 800+ additional state and local law enforcement officers into Los Angeles to clean up President Trump’s mess,” Tara Gallegos, a spokesperson for Newsom, told The Intercept by email.

Experts say that the introduction of the Marines further strains civil-military relations and risks violation of the Posse Comitatus Act: a bedrock 19th-century law seen as fundamental to the democratic tradition in America. The Posse Comitatus Act bars federal troops from participating in civilian law enforcement.

“This is obviously an extreme escalation that is going to pour gasoline on an already combustible situation,” said Elizabeth Goitein, senior director of the Brennan Center’s liberty and national security program. “It’s almost inevitable that the Marines are going to be laying hands on civilians and exercising the kinds of coercive powers that would normally be illegal under the Posse Comitatus Act.”

The Trump administration is attempting to justify its escalatory tactics by claiming people protesting his anti-immigration agenda constitute a rebellion or threaten to become one.

The directive signed by Trump, calling up the Guard, cites “10 U.S.C. 12406,” a provision within Title 10 of the US Code on Armed Services that allows the federal deployment of National Guard forces if “there is a rebellion or danger of a rebellion against the authority of the Government of the United States.”

“Task Force 51 is now comprised of approximately 2,100 National Guard soldiers in a Title 10 status and 700 active-duty Marines,” according to NORTHCOM and have “been trained in de-escalation, crowd control, and standing rules for the use of force.”

The Marines “have the same task and purpose as the National Guard,” said another defense official who spoke with The Intercept on the condition of anonymity in order to speak freely. “You can think of them as an additional force to do the same thing. They just happen to be active-duty Marines. But all of the troops in total who are doing this are all activated under Title 10.”

Goitein disputes that Marines can be employed under the same authority as the National Guard. “Legally, they can’t rely on the same authority. They’re not in the same position legally,” she said. Title “10 U.S.C. 12406 applies to the National Guard. It doesn’t apply to the active-duty armed forces.”

Goitein also pointed to the cultural difference and the public perceptions that separate National Guard troops from the active-duty armed forces. “Active-duty troops, like these Marines, are full-time professional soldiers. The National Guard, at least historically, have been citizen-soldiers who are in their communities during the week and training on weekends,” she told The Intercept. “For Californians, Los Angelenos, who are facing these Marines, it feels different and to some degree it is different.”

A few hundred of the 2,000 National Guard troops called up to serve in Los Angeles are already in the city as federal agents and people protesting immigration raids faced off for a fourth day on Monday. Protests, as of the afternoon, were largely orderly and peaceful.

“Mobilizing Marines against their neighbors is a profoundly dangerous escalation. This deployment is plainly illegal, and it points to the reason why we have laws against these deployments in the first place,” Sara Haghdoosti, the executive director of Win Without War, told The Intercept. “Not only is it an authoritarian power grab, it also threatens the physical health of people exercising their constitutional rights to protest and to the moral health of Marines now ordered to suppress those rights.”

On the streets of Los Angeles on Monday afternoon, Steve Hill, a protester who said he is a Marine Corps veteran, said service members should know better. “Whoever the commanding officer is should know that we don’t follow orders that are unlawful. We follow lawful orders,” he said. “The Marines are not for the streets of America.”