We seem to have entered an era of government snooping and censorship unsurpassed even by the dismal standard set four decades ago by President Richard Nixon.

In recent days, we have discovered that the Internal Revenue Service targeted conservative groups, the Justice Department went after journalists at the Associated Press and Fox News, and the National Security Agency has been aggregating records of our phone calls and online activities. Taken together, this behavior has all the hallmarks of a paranoid, totalitarian regime, regardless of whether President Barack Obama’s administration takes legal comfort by claiming cover under the overreaching Patriot Act.

There have also been some less headline-grabbing incidents of unchecked power that seem almost quaint (but are no less appalling): Billionaires who use their money and power to influence what gets shown, or not, on public television.

Consider the sorry saga of “Citizen Koch,” an independent documentary film that traces the effect of the tidal wave of corporate money that has flooded the political system since the Supreme Court’s 2010 Citizens United decision. In April 2012, the two filmmakers behind “Citizen Koch” -- Tia Lessin and Carl Deal -- received $150,000 from Independent Television Service, a San Francisco-based outpost of public television that gets funding from the Corporation for Public Broadcasting to support and distribute independent films.

Wisconsin Recall

Using the 2012 Wisconsin recall election as a tableau, “Citizen Koch” fairly and accurately portrays the way big money, much of it from out of state, was used to help the Republican governor, Scott Walker, retain his office.

The title of the film is partly a play on “Citizen Kane,” Orson Welles’ thinly veiled portrait of William Randolph Hearst. It also refers to the documentary’s description of the role played in the recall election by Americans for Prosperity, a so- called super-PAC funded by David and Charles Koch, the ultraconservative billionaire owners of Koch Industries Inc. The Bloomberg Billionaires Index pegs the brothers as being worth $43.7 billion each, making them the sixth and seventh richest people in the world.

“Citizen Koch” features a number of brief interviews with Tim Phillips, the president of Americans for Prosperity, and allows him to explain his thinking about why the Kochs were focused on the Wisconsin recall election. This has the effect of hoisting him on his own petard, at least from the perspective of a jaded New Yorker. Neither Koch brother appears in the film, despite a number of e-mailed invitations from Lessin and Deal.

It turns out that David Koch, for whatever reason, is a fan of public television. Over the years, he has donated $23 million for shows and independent films that have -- how shall we say? - - a more liberal-leaning view of the world. In 1997, Koch became a trustee of WGBH, the public television station in Boston, and in 2006, he joined the board of WNET, in New York City.

In 2012, all seemed well between the filmmakers and ITVS, which had seen a rough cut and enthusiastically supported the film. Then, by coincidence, another documentary film -- “Park Avenue: Money, Power and the American Dream” -- by Academy Award-winning filmmaker Alex Gibney was scheduled to debut Nov. 12 on PBS. In his film -- as in Michael Gross’s earlier book “740 Park: The Story of the World’s Richest Apartment Building” -- Gibney used 740 Park Avenue as a metaphor for the wealth and power that is concentrated in Manhattan. The building’s wealthiest resident is David Koch, and, in the film, Gibney referred to him as a “right-wing oil tycoon,” explained that Koch Industries paid what was then “the largest civil penalty” in the history of the Environmental Protection Agency, and, perhaps most damning, revealed that the billionaire had tipped a doorman a mere $50 at Christmas, writing a check.

Donation Drive

According to Jane Mayer, who broke this story last month in the New Yorker, David Koch wasn’t happy about his portrayal and let Neil Shapiro, the president of WNET, know about it. Complicating matters, according to Mayer, was WNET’s expectation that David Koch would donate at least $1 million to its capital campaign.

Mayer wrote that Shapiro attempted to “mollify” Koch by giving him a heads-up about the film, organizing a roundtable debate, and adding a voice-over introduction warning that it was “controversial” and “provocative.” Gibney’s film aired as scheduled but, according to Mayer, Koch canceled whatever plans he had to make a large donation to WNET. (He resigned from the WNET board on May 16; he remains on the board of WGBH.)

That’s how “Citizen Koch” became caught in the crossfire between David Koch and WNET and ITVS. A public-relations official told Mayer that airing “Citizen Koch” on public television “was a real problem, because of ‘Park Avenue.’ Because of the whole thing with the Koch brothers, ITVS knew WNET would never air it. Never.”

ITVS, for its part, couldn’t risk alienating WNET, which has the largest public television audience. On April 15, ITVS told Lessin and Deal that it was pulling the plug on its support for “Citizen Koch.”

“We were stunned,” Lessin told me in a recent interview. “It’s not outright control. They’re just fostering a kind of self-censorship that happens when the public television executives and programmers are guided by what they believe will please or anger the very donors that they rely on.”

Lessin and Deal lost a major portion of their funding and are now paying for the film out of pocket. Some of their vendors haven’t been paid but have been understanding, so far. They also lost their distribution network and a chance for a wider audience to see the film. “Citizen Koch” has been shown at film festivals, but that’s it.

“Look, we’ve suffered,” Lessin said. “The film has suffered. The public television audience doesn’t get to see the film. Now, looming on the horizon, David Koch and Charles Koch seem to be interested in purchasing the Tribune Company newspapers. If they can have the influence over our film -- just by David Koch being on the board of trustees and being a donor - - imagine the influence that they would have if they actually owned these really important papers.”

And, just like that, in this insidious way -- a film censored here, some phone records seized there -- the freedoms that we once took for granted and thought were guaranteed by our Constitution are slowly but surely eroded. This can’t be a good thing.

(William D. Cohan, the author of “Money and Power: How Goldman Sachs Came to Rule the World,” is a Bloomberg View columnist. He was formerly an investment banker at Lazard Freres, Merrill Lynch and JPMorgan Chase.)