If you haven’t been following the story of the Agenda 21 conspiracy theory, here’s a quick overview. Some people believe a two-decade-old, non-binding UN plan to promote sustainable development means the government is going to seize their land and cars and force them to live in tenements. The ultra-conservative John Birch Society says that Agenda 21 “seeks to curtail your freedom to travel as you please, own a gas-powered car, live in suburbs or rural areas, and raise a family.”

Despite its complete detachment from reality, the conspiracy theory seems to have influence and staying power. The Republican National Committee has condemned Agenda 21. The state of Tennessee passed a resolution against it (one legislator even said it would result in “forced abortions“). Colorado gubernatorial candidate Dan Maes infamously cited Agenda 21 as the basis of his opposition to Denver’s bike-share system. Tea Party adherents convinced that smart growth projects are a threat to their liberties have disrupted planning meetings all over the country. In Maine, Republican Governor Paul LePage halted an award-winning transportation and land use plan after one such outburst, though state officials denied that the decision was influenced by the conspiracy theorists.

Overall, a small percentage of Americans have been taken in by Agenda 21 paranoia, according to a survey commissioned by the firm Collective Strength, which does market research for many smart growth-related organizations. They found that 85 percent of Americans had never heard of Agenda 21, and only six percent oppose it.

“I genuinely believe the Agenda 21 phenomenon is highly manufactured,” Collective Strength’s Robin Rather told TreeHugger. “It’s not out there in the mainstream.”

She continued:

Usually when you listen to complaints like those of Tea Party members, there are different inflections, a much wider variation. But this isn’t organic and local, the same talking points come up everywhere. They are being played and used. The whole campaign serves no interest to anyone who isn’t trying to ensure that we keep burning as much fossil fuel as we can for as long as possible.

So who’s manufacturing the paranoia?

TreeHugger’s Lloyd Alter runs through the cast of characters on the Agenda 21 speaking circuit. They are a small group of people affiliated with a handful of outfits with strong ties to the fossil fuel industry.

A major player is Tom DeWeese, president of the American Policy Center, which Alter calls the “loudest mouthpiece of the Agenda 21 conspiracy crowd.” DeWeese’s conspiracy-fueled “expertise” is propagated by far-right groups including the John Birch Society, the Conservative Political Action Committee, and Americans for Prosperity — which was founded thanks to the fossil fuel-generated wealth of the Koch brothers. DeWeese’s board includes several veterans of the dirty energy industry’s campaign to discredit the scientific consensus on global warming.

For more on the ties between the Agenda 21 conspiracy mongers and the fossil fuel industry, Alter’s full piece is worth a read. Ultimately, he says, disarming the misinformation campaign will depend on exposing these connections.