A presidential inauguration is usually a time for celebration. This year, however, it may look something like the beginning of a low-scale civil war.

And while the events of the next couple of days are expected to pose an unprecedented challenge for law enforcement, the "civil disobedience" promises to extend far beyond Inauguration Day.

Thanks to the outgoing Obama administration, according to an expert.

This year, militant left-wing protesters have vowed to sabotage public transportation and attack people with "throat punching" to cause chaos at President-elect Trump's inauguration. An undercover investigation also revealed a plot to use butyric acid against a gathering of Trump supporters.

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One self-described anarchist group involved with the #DisruptJ20 events, "Crimethinc," claims the goal is not just to cause chaos but to politically cripple the new president.

"[I]f the demonstrations interfere with the inauguration and the maintenance of order, that will help to normalize the kind of resistance that will be necessary to prevent Trump from implementing his agenda," the group threatens.

But one of the nation's foremost law-enforcement specialists and police advocates says it is the outgoing administration that has already normalized disorder and rioting.

Jeff Roorda, former Democratic elected official, executive director of the St. Louis Police Officers Association and author of "The War On Police: How the Ferguson Effect Is Making America Unsafe," said President Obama and his administration have already unleashed dangerous forces in American life.

"The Obama administration, from top to bottom, has glamorized unlawful, riotous demonstrations as some sort of righteous social movement to be adored and coddled," he told WND. "Not so, not in a land of law and order that recognizes that one American's freedoms end when they infringe on the peaceful existence of another American."

As Breitbart has reported, anarchist websites are urging demonstrators to "go hard" because "this is our only chance to fight Trump under the laws and police protocol of the Obama era."

"The words 'go hard' scare me," Roorda said. "It sounds to me like a dog whistle meant to signal violence to those given to lawlessness, the types of people whom we've seen act with impunity at other ugly protests across the country."

It's never been tougher to be one of the men in blue than it is right now. Get "The War On Police: How the Ferguson Effect Is Making America Unsafe" now at the WND Superstore

Because of a law urged by the ACLU, police will not be turning on their body cameras during the protests, thus potentially allowing violent demonstrators to get away with committing crimes.

The website DisruptJ20.org, which is serving as an organizing point for the dozens of groups expected to cause trouble at the event, urged people to "wear all black" and gather at Logan Circle at 10 a.m. the day of the ceremony.

"Those who travel to DC to celebrate Trump's ascendance to power will find the inaugural ceremonies reduced to a total [expletive]," the group boasts. "Many different marches, blockades, and other autonomous direct actions are planned."

The instruction to wear all black is likely an endorsement of the "black bloc" tactic, a common practice of anarchist groups in which they dress in similar clothing and mask their face to make it difficult for law enforcement to stop them from committing crimes.

As the website Crimethink puts it, "Acting in a bloc is especially useful when some of the participants in the action expect they may break laws."

"Getting away with public criminal acts" is described as one of the most important benefits of the tactic, as well as how "empowering" it is for participants.

Roorda hopes the beginning of the Trump administration means an end to tolerance of such practices by the federal government.

"I expect the same thing from President Trump that I expect from any president," said Roorda. "I expect the Trump administration and the Sessions' Justice Department to enforce and honor the law. The law requires them to hold police departments accountable, which is good, but it doesn't give the feds license to invent new, unreasonable criterion that hold police officers to an idealized, impossible standard. The law also requires that protests not be disruptive to civil society.

"I expect everything from minor disruptions to riots, looting, arson and police ambushes to be met with the full force of law and the full force of the federal government."

Roorda admitted every group, no matter how extreme, has the right to protest lawfully and be heard. But he blasted the idea a "black bloc" or any other group dedicated to criminal activity should be given a pass.

"The moment anyone, and I mean anyone, in the crowd resorts to violence, it is no longer a 'peaceful protest' and shouldn't be treated as such," he said. "Those engaged in violence should be identified and arrested as should anyone who gets between them and the police. If the violent actors can't be identified or apprehended, the entire demonstration should be shut down with swift and decisive action."

Interim Metropolitan Police Chief Peter Newsham assured Americans the police would be able to control the protests. But Roorda said police will need more than just assurances: Enforcing the law sometimes requires an unapologetic display of force.

"Any group of Americans no matter how misguided or unpatriotic has a right to express themselves publicly, even when they're dead wrong," Roorda said. "But unlawful activity should be met with consequences; violence should be met with force; and lies should be met with truth. We have to stop rewriting history because what really happened hurts the feeling of a small group of dissidents. That's why I wrote my book, 'The War on Police,' to set the record straight on the 'hands up, don't shoot' myth. Ultimately, these groups lose steam when the credibility of their chants are contradicted by the harsh reality of incontrovertible evidence."

It's never been tougher to be one of the men in blue than it is right now. Get "The War On Police: How the Ferguson Effect Is Making America Unsafe" now at the WND Superstore

There's also a new movie appearing on Thursday, "America Under Seige: Civil War 2017," a documentary that exposes the left-wing groups who are demonstrating. And what they likely are planning far into the future.

The film is the first episode in a five-part "America Under Siege" documentary web-series to be released over the course of 2017. Each episode will profile the influence of radical Marxists on various segments of American society. The first episode will be available for free on DangerousDocumentaries.com or at CapitalResearch.org.

See the trailer:

Director Judd Saul and conservative commentator Trevor Loudon have compiled a team of researchers and undercover operatives to probe the roots of the anti-Trump movement, highlighting the ultimate goals and ulterior motives.

"We're a non-profit and that informs our operations, but we believe that making films for conservatives and libertarians is currently a major missed business opportunity by the film industry," said Dangerous Documentaries founder Joseph Klein. "We intend to demonstrate that quality content for this audience can be highly profitable, and hope to encourage more investment targeting this market by doing so."