The founder of a far-right militia once warned of federal tyranny. Then came Trump.

"At the core of the anti-government movement is conspiracy theories," said Freddy Cruz, a Southern Poverty Law Center analyst who studies the Oath Keepers.

Stewart Rhodes, founder of the far-right militia the Oath Keepers, speaks during a rally outside the White House on June 25, 2017.Susan Walsh / AP file

WASHINGTON — Nearly two decades ago, Stewart Rhodes won an award at Yale Law School for his paper arguing that the Bush administration's use of "enemy combatant" status to detain Americans indefinitely was unconstitutional.

Tolerating such a violation, he asserted, would be like leaving out "a loaded weapon — a perpetual threat to our liberties — to be picked up by the next overzealous, overconfident and willful president."

But in the weeks after the 2020 election, presidential overreach seemed far from his mind. In an open letter on the website of the Oath Keepers, the far-right militia group he founded in 2009, Rhodes urged President Donald Trump to invoke the Insurrection Act, send special forces to seize state elections systems, redo the election and deploy both the National Guard and a self-armed militia to suppress any rebellion from "domestic enemies" in the way.

"If you fail to do so, we the people will have to fight a bloody revolution/civil war to throw off an illegitimate deep state/Chinese puppet regime," he wrote.

In the days before the U.S. Capitol riot, he'd put out a call on the group's website for "all patriots who can be in DC" to travel to the capital for a "security mission" to "stand tall in support of President Trump's fight."

At least three people affiliated with the Oath Keepers have been indicted on conspiracy charges stemming from the riot, including one, Thomas Caldwell of Virginia, who is described in federal court papers as having "a leadership role within the Oath Keepers."

Rhodes' shift isn't entirely unique. The Oath Keepers were one of a variety of militia groups that coalesced around Trump, many of which had previously been highly skeptical of the federal government.

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How Rhodes, 55, went from being a libertarian former Arizona Supreme Court law clerk warning about federal tyranny to calling for the U.S. military to suppress resistance from U.S. citizens offers a window into the evolution of the anti-government groups that embraced Trump as an ally in their existential battle against the government he ran. Some of the groups are heavily armed, and members are being investigated over whether they had roles in the Capitol riot.

For Rhodes and the Oath Keepers, support for Trump — who once claimed that his authority was "total" and whom they initially viewed skeptically — followed a conspiratorial arc in which preparing for confrontation with the government eventually gave way to a more nativist focus on perceived threats to American values by leftist groups, the deep state and supposed foreign conspirators or global cabals.

"That process of falling in line behind Trump was in part because Trump's opponent was Hillary Clinton, and the Clinton name is so anathema to this broader movement," said Sam Jackson, who teaches at the College of Emergency Preparedness, Homeland Security and Cybersecurity at the State University of New York at Albany and wrote the 2020 book "Oath Keepers: Patriotism and the Edge of Violence in a Right-Wing Antigovernment Group."

"Another part is the group has some really virulent strains of Islamophobia and nativism and anti-immigrant sentiment," he said.

Rhodes, who along with the Oath Keepers did not respond to several requests for comment, was photographed at the Capitol that chilly Wednesday, although it's unclear whether he took part in storming the building where he once worked as a staffer for then-Rep. Ron Paul of Texas, a Republican-turned-libertarian.

Elmer Stewart Rhodes was born in California, public records show, He was a paratrooper in the Army until he was severely injured in a parachute accident during a nighttime training jump. According to an archived biography from his website, he enrolled at the University of Nevada, Las Vegas, and volunteered teaching rape prevention at its women's center.

It was after college that he moved to Washington to work for Paul in Congress.

As a student at Yale Law School, he overlapped for two years with President Joe Biden's national security adviser, Jake Sullivan, who didn't respond to an inquiry about whether the two had met in New Haven. After he clerked for Arizona Supreme Court Justice Michael Ryan, Rhodes eventually landed in Montana, where he advertised in the journal Montana Lawyer offering "YALE QUALITY research and brief writing ... Ivy League quality, without Ivy League expense."

He was disbarred after the Montana Supreme Court found that he'd abandoned clients in Arizona, a 2015 court order shows.

By then, Rhodes was several years into the Oath Keepers, which he formed after having volunteered with Paul's unsuccessful 2008 campaign for the Republican presidential nomination.

"I concluded that if I could not help get a constitutionalist into the White House, the least I can do is to remind those in current service of their obligations to refuse unlawful orders, including unconstitutional orders," Rhodes said in 2010 in a interview with the libertarian website The Daily Bell.

Walter Reddy, a gun rights advocate and tea party activist from Connecticut who said he protested peacefully at the Capitol last month, recalled helping secure the permit in 2009 for a rally of militia enthusiasts in Lexington, Massachusetts, where the Oath Keepers held their first gathering and Rhodes presented the group's key tenets: a 10-item list of "unconstitutional" orders that sworn defenders of the Constitution, like law enforcement officials and the military, must never obey.

"I knew he was pretty bright," Reddy said in an interview. "Somebody had told me about him, and I said, 'Yeah, fine.' It was just a blog or something. It sounded OK. I supported our military and police — why not?"

The group took root at the height of the tea party political movement, whose freedom-focused ideology and membership overlapped to some degree with the Oath Keepers. Chapters were formed in all 50 states. By 2014, Rhodes told a newspaper, the group boasted 35,000 members, although estimates by watchdog groups are far lower.

The same year, an armed clash over grazing rights on federal lands in Nevada helped put the Oath Keepers on the map as an operational force, as the group gained prominence by sending members to Cliven Bundy's ranch in support.

Video posted by the organization on YouTube showed Rhodes at the scene helping to move a fence.

But in the years before Trump was elected, the Oath Keepers' focus and rhetoric started shifting from perceived threats to the Constitution posed by the government and political elites to threats from "leftists."

The group inserted itself in hot-button political and social crises, sending armed members to Ferguson, Missouri, in 2015. The Oath Keepers said they were there to protect businesses during the sustained protests over the fatal shooting in 2014 of Michael Brown, a Black teenager, by a white police officer, which helped give birth to the Black Lives Matter movement.

The group offered bodyguards for Kim Davis, the Kentucky county clerk who was jailed for refusing to grant marriage licenses to same-sex couples. She declined the offer.

Trump's emergence as the protagonist in the group's narrative about a fight against tyranny wasn't ordained. When Trump signaled openness to stricter gun laws in a debate against Clinton in September 2016 — "You take the gun away from criminals that shouldn't be having it" — the Oath Keepers recoiled, calling Trump out on their website for making "unacceptable concessions" and waving "another red flag."

But by the time voters cast their ballots two months later, the group had issued a "call to action" to members to position themselves at polling places as both it and Trump ominously warned about massive fraud, voter intimidation and potential violent unrest if he was elected. And after Trump took office, it began sending members to his re-election rallies to "escort" supporters whom it claimed faced violence from Black Lives Matter or antifa supporters.

As America braced for Election Day in 2020, the Oath Keepers laid out a marker in advance, asserting that if Trump lost the election, it had to have been rigged, echoing the conspiracy theory Trump was pushing.

Freddy Cruz, an analyst who studies the Oath Keepers for the Southern Poverty Law Center, a nonprofit monitor of hate groups, said the group's ultimate acquiescence to Trump was emblematic of how other purportedly anti-government groups have veered into far-right extremism in recent years in a deluge of disinformation, much of it online, and appeals to xenophobia about Muslims and immigrants that Trump tapped into regularly.

"At the core of the anti-government movement is conspiracy theories," he said. "It's this fear that individuals in power every day are trying to sell away American sovereignty to some foreign entity or erase American identity."

In an interview in 2009 on MSNBC's "Hardball with Chris Matthews," Rhodes disputed that the group had partisan leanings or that he was putting his members on a war footing.

"We're not talking about asking them to go fight. We're saying simply, 'Don't fight,'" Rhodes said. "It's simply saying they're not going to comply with orders that violate the rights of the American people."

Yet, speaking soon after that interview to a fringe website, he seemed to foreshadow how the distrust of government underpinning his movement had the potential to culminate, years later, in a deadly assault on the seat of government.

"I sometimes get angry emails from frustrated people asking, 'When is the military going to march on D.C. and clean out that den of vipers?'" Rhodes said. He said he responded by asking them whom the Constitution designates to suppress insurrections and repel invasions, and he added: "It is not the standing army. It is the militia. And who are the militia? We, the people."