WASHINGTON >> The founder of the Oath Keepers extremist group was sentenced today to 18 years in prison for orchestrating a weekslong plot that culminated in his followers attacking the U.S. Capitol in a bid to keep President Joe Biden out of the White House after the 2020 election.

Stewart Rhodes is the first person charged in the Jan. 6, 2021, attack to be sentenced for seditious conspiracy, and his sentence is the longest that has been handed down so far in the hundreds of Capitol riot cases.

It’s another milestone for the Justice Department’s sprawling Jan. 6 investigation, which has led to seditious conspiracy convictions against the top leaders of two far-right extremist groups authorities say came to Washington prepared to fight to keep President Donald Trump in power at all costs.

Before handing down the sentence, the judge told a defiant Rhodes that he is a continued threat to the U.S., saying it’s clear Rhodes “wants democracy in this country to devolve into violence.”

“The moment you are released, whenever that may be, you will be ready to take up arms against your government,” U.S. District Judge Amit Mehta said.

It was one of the most consequential cases brought by the Justice Department, which has sought to prove that the riot by right-wing extremists like the Oath Keepers was not a spur-of-the-moment protest but the culmination of weeks of plotting to overturn Biden’s election victory.

Prosecutors had sought 25 years for Rhodes, who they say was the architect of a plot to forcibly disrupt the transfer of presidential power that included “quick reaction force” teams at a Virginia hotel to ferry weapons into D.C. if they were needed. The weapons were never deployed.

In remarks shortly before the judge handed down the sentence, Rhodes slammed the prosecution as politically motivated, noted that he never went inside the Capitol and insisted he never told anyone else to do so.

“I’m a political prisoner and like President Trump my only crime is opposing those who are destroying our country,” Rhodes said.

In a first for a Jan. 6 case, U.S. District Judge Amit Mehta agreed with prosecutors to apply enhanced penalties for “terrorism,” under the argument that the Oath Keepers sought to influence the government through “intimidation or coercion.” Judges in previous sentencings had shot down the Justice Department’s request for the so-called “terrorism enhancement” — which can lead to a longer prison term — but Mehta said it fits in Rhodes’ case.

Prosecutors argued that a lengthy sentence is necessary to deter future political violence. Assistant U.S. Attorney Kathryn Rakoczy pointed to interviews and speeches Rhodes has given from jail repeating the lie 2020 election was stolen and saying it would be again in 2024. In remarks just days ago, Rhodes called for “regime change,” the prosecutor said.

People “across the political spectrum” want to believe that Jan. 6 was an “outlier,” Rakoczy said. “Not defendant Rhodes.”

A lawyer for Rhodes, who plans to appeal his conviction, said prosecutors are unfairly trying to make Rhodes “the face” of January 6. Attorney Phillip Linder told the judge that Rhodes could have had many more Oath Keepers come to the Capitol “if he really wanted to” disrupt Congress’ certification of the Electoral College vote.

“If you want to put a face on J6 (Jan. 6), you put it on Trump, right-wing media, politicians, all the people who spun that narrative,” Linder said.

Another Oath Keeper convicted alongside Rhodes in November — Florida chapter leader Kelly Meggs — was expected to receive his sentence later today.

Two other Oath Keepers, acquitted of the sedition charge but convicted of other offenses, will be sentenced Friday. And four other members found guilty of seditious conspiracy at a second trial in January are scheduled to be sentenced next week.

The convictions were a major blow for the Oath Keepers, which Rhodes founded in 2009 and grew into one of the largest far-right anti-government militia groups. Recruiting past and present members of the military and police officers, the group promotes the belief that the federal government is out to strip citizens of their civil liberties and paints its followers as defenders against tyranny.

Rhodes’ sentence may forecast what prosecutors will seek for former Proud Boys national chairman Enrique Tarrio, who was convicted of seditious conspiracy alongside other leaders of his far-right group this month for what prosecutors said was a separate plot to block the transfer of presidential power. The Proud Boys will be sentenced in August and September.

Rhodes, 58, and the other Oath Keepers said there was never any plan to attack the Capitol or stop Congress from certifying Biden’s victory. The defense tried to seize on the fact that none of the Oath Keepers’ messages laid out an explicit plan to storm the Capitol. But prosecutors said the Oath Keepers saw an opportunity to further their goal to stop the transfer of power and sprang into action when the mob began storming the building.

Messages, recordings and other evidence presented at trial show Rhodes and his followers growing increasingly enraged after the 2020 election at the prospect of a Biden presidency, which they viewed as a threat to the country and their way of life. In an encrypted chat two days after the election, Rhodes told his followers to prepare their “mind, body, spirit” for “civil war.”

In conference call days later, Rhodes urged his followers to let Trump know they were “willing to die” for the country. One Oath Keeper who was listening was so alarmed that he began recording the call and contacted the FBI, telling jurors “it sounded like we were going to war against the United States government.”

Another man testified that after the riot, Rhodes tried to persuade him to pass along a message to Trump that urged the president not to give up his fight to hold onto power. The intermediary — who told jurors he had an indirect way to reach the president — recorded his meeting with Rhodes and went to the FBI instead of giving the message to Trump. Rhodes told the man during that meeting that the Oath Keepers “should have brought rifles” on Jan. 6.

Before today, the longest sentence in the more than 1,000 Capitol riot cases was 14 years for a man with a long criminal record who attacked police officers with pepper spray and a chair as he stormed the Capitol. Just over 500 of the defendants have been sentenced, with more than half receiving prison time and the remainder getting sentences such as probation or home detention.