As riots rage across Los Angeles, President Donald Trump’s decision to mobilize military forces has become a focal point for controversy. Golden State Governor Gavin Newsom (D) even filed a lawsuit demanding that a federal court block the president’s federalization of the California National Guard. On Tuesday, however, Judge Charles Breyer of the U.S. District Court for the Northern District of California, a Clinton appointee, rejected Newsom’s petition for an ex parte emergency injunction, instead agreeing to give the Trump administration time to craft and present arguments in the case.

Newsom and his Attorney General, Rob Bonta (D), argued in their initial petition, “One of the cornerstones of our Nation and our democracy is that our people are governed by civil, not military, rule.” They accused the president of invoking “emergency powers to exceed the bounds of lawful executive authority” and “make another unprecedented power grab, this time at the cost of the sovereignty of the State of California and in disregard of the authority and role of the Governor as commander-in-chief of the State’s National Guard.”

But a majority of Americans disagree with Newsom’s and Bonta’s assertions. An Insider Advantage poll conducted Monday and Tuesday found that nearly 60% of Americans support the president’s federalization of the California National Guard and deployment of U.S. Marines in Los Angeles, as opposed to only 39% who disapprove. Unsurprisingly, 89% of Republican voters back the president, but so do a majority (56%) of Independent voters and over a third (37%) of Democrat voters.

Amid the controversy, the president himself decided to explain his decision to federalize the National Guard, pointing to his experience during the infamous riots of summer 2020. “I’ve been here before, and I went right by every rule,” Trump told reporters in the Oval Office on Tuesday. He explained, “I waited for governors to say, ‘Send in the National Guard.’ They wouldn’t do it … I said to myself, ‘If that stuff happens again, we’ve got to make faster decisions.’” He further intimated that he may invoke the Insurrection Act if violence continues in L.A. “If there’s an insurrection, I would certainly invoke it,” the president stated. “If we didn’t get involved, right now Los Angeles would be burning, just like it was burning a number of months ago,” he added, referring to the wildfires that ravaged southern California earlier this year.

Appearing on Tuesday night’s episode of “Washington Watch,” Senior Fellow for Homeland Security and Immigration at the Center for Renewing America and Acting Deputy Secretary of Homeland Security during Trump’s first term Ken Cuccinelli recommended that the president invoke the Insurrection Act. “It’s called the Insurrection Act, and the media loves that name because it sounds so inflammatory. But insurrection is only one of the four bases on which the president can invoke the powers found in the Insurrection Act,” Cuccinelli explained. He continued, “Others are just illegal assemblies, conspiracies, and so forth. And we clearly have that going on here where violence occurs and constitutional rights, including property rights, are impaired, and we’re way past that threshold in Los Angeles.”

“It’s not a high legal threshold for the president. If the president decides that federal resources available are insufficient to accomplish the execution of federal law like deportations by ICE agents, then he may use the Insurrection Act to supplement those forces,” Cuccinelli noted. He added, “And in that situation, the U.S. Marines can make arrests, they can join the ICE agents in doing their job, as can the National Guard members. So that hasn’t happened yet, but that is something the president seems in his comments to be preparing America for.”

As Cuccinelli observed, the president’s use of military forces for the purposes of domestic law enforcement and riot control is far from unprecedented. In 1863, President Abraham Lincoln famously used U.S. Army forces to stamp out the New York City draft riots. As the American Civil War was beginning, New York City was home to a significant immigrant population — predominantly Irish and German — who were quickly granted citizenship by Democratic Party officials in order to vote for the Democrats’ ruling Tammany Hall elites. New York also relied heavily on southern states for economic purposes, with almost half of the port city’s exports being cotton from southern plantations.

When Congress passed the Enrollment Act, establishing the first federal draft, New Yorkers rose up in protest, quickly turning to rioting. European immigrants in the city were already dismayed by the Emancipation Proclamation, fearing that freed slaves would migrate to New York en masse and overwhelm the already-fraught labor market but were doubly angered when black free men in the city were exempt from the draft, not yet being considered U.S. citizens. Matters were worsened when New York City’s wealthy elites were permitted to opt out of the draft for a fee of $300, the equivalent of nearly $8,000 today.

Rioting began on July 13, when a crowd of 500 laid siege to the assistant Ninth District provost marshal’s office, where the drawing of draft numbers was taking place. Rioters smashed windows, set the building on fire, and cut telegraph wires to ensure the rest of the city was not notified of the riot. It fell to the New York Police Department (NYPD) to quell the rioting, as the state’s militia (the precursor to the National Guard) was fighting in the Battle of Gettysburg. NYPD superintendent John Kennedy was assaulted and left with at least 70 knife wounds. The mob grew and the riot spread, burning down police stations, newspaper offices, and businesses, brutally beating black civilians, raiding orphanages and food pantries, and driving NYPD forces back.

Under the Militia Act of 1792 — not the Insurrection Act of 1807 or its 1861 update — Lincoln mobilized U.S. military forces, including Army soldiers and Marines, to join recalled state militia forces in controlling the riots. Many of the soldiers had just returned from the bloody Battle of Gettysburg. By the time that order was restored on July 16, the official death toll stood at 120, although some historians estimate that as many as 1,200 rioters, civilians, and soldiers were killed over the course of the four-day riot. Historian James McPherson estimated that no less than 119 were killed, while historical journalist Herbert Asbury stipulated that at least 2,000 were killed and over 8,000 were wounded. All told, over 4,000 U.S. military troops were diverted from Gettysburg to New York City to halt the rioting.

Following the Civil War, President Ulysses S. Grant, who had led the Union to victory, deployed U.S. military forces extensively throughout the South to maintain law enforcement. Upon ascending to the White House, Grant was faced with widespread violence and chaos in the South, predominantly led by the Ku Klux Klan (KKK). Both freed slaves and Republicans were routinely targeted for beatings, whippings, lynchings, and other forms of murder, and the KKK and other partisans regularly relied on violence and intimidation to rig elections, preventing black citizens and Republicans from voting. Relying on the Insurrection Act, Grant stationed an estimated 20,000 U.S. Army troops in the South, out of a total force of less than 30,000 Army troops nationwide. The Enforcement Acts of 1870 and 1871 gave the president even broader authority to use military force for domestic law enforcement purposes.

Grant used U.S. military forces, alongside U.S. marshals, to oversee federal elections in Alabama, the Carolinas, Georgia, Louisiana, Mississippi, and Virginia. Soldiers would be stationed at polling places in an attempt to counter election fraud, intimidation, and the violence enacted by the KKK, Red Shirts, White League, Knights of the White Camelia, and other Democrat militia and paramilitary groups. In many cases, federal forces were required to restore order following controversial elections in which both Republicans and Democrats claimed victory and legitimacy. In 1872, for example, the hotly-contested Louisiana gubernatorial race culminated in the Battle of Liberty Place, alternatively known as the Battle of Canal Street, when White League insurgents staged an insurrection in New Orleans, which was then the capital of Louisiana. The rebels took over the statehouse and many key locations, which they held for three days before retreating when Grant ordered U.S. Army troops to New Orleans.

The Army was also used to dismantle KKK networks throughout the South, especially in Alabama, South Carolina, and Tennessee. Small garrisons, typically of between 500 and 1,000 troops, were established across the South, and Army soldiers would both serve as protection for black citizens and white Republicans, who were often targeted for torture and murder by the KKK, and assist U.S. marshals in hunting down and arresting KKK cells and leaders. The violence was so excessive — hundreds of black citizens and white Republicans were murdered, and local courts often dropped charges or suspended sentences against Klansmen — that Grant quickly suspended habeas corpus.

Grant’s use of federal military might in the South, though legal, fueled resentment amongst Southerners, including those who did not support the KKK or its activities. In 1878, Grant’s successor, President Rutherford B. Hayes, signed the Posse Comitatus Act into law, which placed heavy restrictions on the president’s use of the military for law enforcement purposes, particularly relating to the regulation of elections, “except in such cases and under such circumstances as such employment of said force may be expressly authorized by the Constitution or by act of Congress,” such as under the auspices of the Insurrection Act.

Ironically, Hayes’s own use of federal forces contributed to support for the Posse Comitatus Act’s passage. During the Great Railroad Strike of 1877, which included over 50 consecutive days of strikes, rioting, violence, and arson, Hayes mobilized U.S. Army soldiers against strikers in Illinois, Maryland, Missouri, New York, Pennsylvania, and West Virginia. Army troops, including those who had just been stationed throughout the South under Grant’s authority, marched from city to city suppressing riots and breaking strikes.

However, President Grover Cleveland would also use the Army as a strikebreaking instrument just a few years later. In 1894, the Pullman Strike shut down almost all of the nation’s freight and passenger railway traffic west of Detroit for over two months. Citing his presidential authority to protect federal property — namely, the delivery of U.S. mail — Cleveland mobilized thousands of Army troops to Chicago to break the strike. Soldiers then continued marching city to city, violently breaking strikes. Notably, the president did not invoke the Insurrection Act, and Illinois’s Democratic governor John Altgeld challenged the legality of Cleveland’s actions, demanding a withdrawal of federal forces from the state. Cleveland and his attorneys, however, pointed to the president’s constitutional obligation to ensure mail delivery and protect federal property as the basis for federal military intervention.

Presidents continued to use military force domestically throughout the 20th century too. In 1932, a group of 43,000 World War I veterans, their family members, and various supporters marched on Washington, D.C. and set up an encampment, demanding early cash redemption of certificates promising military service bonuses. When Washington police forces failed to disperse the protestors, nicknamed the Bonus Army, President Herbert Hoover sent General Douglas MacArthur and then-Major George S. Patton to lead an estimated total of 2,000 U.S. Army troops, including cavalry and tanks, into Washington. The Bonus Army initially thought that the soldiers were there in a show of support or solidarity — until Patton led the cavalry in a charge on the protestors. Once again, the Insurrection Act was not invoked.

However, subsequent uses of military force for domestic law enforcement purposes or riot control often relied on the Insurrection Act. In 1957, President Dwight D. Eisenhower federalized the Arkansas National Guard and deployed the U.S. Army’s 101st Airborne Division to desegregate a Little Rock high school citing the Insurrection Act and Democratic Governor Orval Faubus’s refusal to comply with federal civil rights laws. Five years later, President John F. Kennedy would also invoke the Insurrection Act to federalize National Guard units and use U.S. Army soldiers to enforce desegregation in Mississippi and Alabama.

Kennedy’s vice president and presidential successor, Lyndon B. Johnson, would also invoke the Insurrection Act on multiple occasions. In 1965, Johnson deployed federal troops to provide security for Martin Luther King, Jr.’s civil rights marches in Alabama, after state and local authorities failed to prevent violence against the demonstrators. In 1967, Johnson would send 5,000 U.S. Army soldiers to Detroit to crush race riots. Just one year later, in 1968, Johnson would again use the Insurrection Act to justify large-scale military deployments to quell the riots which followed King’s assassination. Nearly 12,000 Army soldiers and Marines were stationed in Washington, D.C. alone, while 5,000 Army troops were sent to Chicago, and over 5,000 were deployed to Baltimore.

The Insurrection Act was used several times over the next almost-35 years, often when a president federalized a state’s National Guard to quash a riot or disperse a protest that had gotten out of hand, such as anti-Vietnam War demonstrations, or for other, non-combative domestic purposes. President Richard Nixon, for example, employed U.S. armed forces during the 1970 U.S. Postal Strike, but soldiers were tasked with sorting and delivering mail, not putting down a rebellion. President Ronald Regan would deploy Delta Forces to control a prison riot at a federal penitentiary in Georgia in 1986. But no significant use of U.S. military forces domestically would be seen again until 1992.

In 1991, a black man named Rodney King was viciously beaten by four Los Angeles Police Department (LAPD) officers after leading them on a high-speed drunk-driving chase through L.A. The nasty ordeal was caught on tape and, when the officers were acquitted in 1992, the city erupted in chaos. When black L.A. residents began engaging in criminal conduct — refusing to pay for gas station purchases, smashing windows, and throwing rocks at law enforcement officers — police responded aggressively, inflaming tensions and resulting in four days of rioting, looting, arson, assault, and violence. A state of emergency was declared and a curfew imposed. L.A. residents of Korean descent were targeted by rioters, and “rooftop Koreans” defended their homes and businesses, perching on roofs with sniper rifles, shotguns, and automatic weapons.

Then-Governor Pete Wilson mobilized the National Guard, but soon afterwards requested federal assistance. President George H.W. Bush dusted off the Insurrection Act and sent 1,500 U.S. Marines and 2,000 U.S. Army soldiers to put a stop to the chaos and destruction. In the end, 63 people were killed, including one person shot by the National Guard, over 2,300 were injured, and over 1,100 buildings were burned to the ground, with property damage and material losses approaching $1 billion.

Fast-forward 32 years, and L.A. is at it again, with thousands of rioters waving foreign flags, assaulting local and federal law enforcement agents, dropping concrete slabs on police cars, launching fireworks and Molotov cocktails at LAPD and federal forces, and setting the city on fire. Trump’s decision to federalize California’s National Guard and deploy hundreds of U.S. Marines — with or without the backing of the Insurrection Act — is far from unprecedented. In fact, the presence of federal military forces may become an even more common feature across the nation. Texas Governor Greg Abbott (R) has already summoned the Lone Star State’s National Guard, anticipating unrest as anti-immigration riots ramp up in Texas, and left-wing activists are reportedly planning over 1,500 “No Kings” protests on June 14. Anti-immigration protests, some of which are already spiraling into riots, have also sprung up in Atlanta, Chicago, Omaha, and New York City.

If state authorities follow in Newsom’s footsteps in response to riots, Trump may choose to follow in the footsteps of Hayes and Cleveland and send the military from city to city, not breaking strikes but riots.