Precisely at noon on March 19, 1979, six newly installed video cameras went live in the gallery of the House chamber for the first time. Washington was never the same.

That broadcast, about to mark its 40th anniversary, launched the Cable-Satellite Public Affairs Network.

C-SPAN is now such a ubiquitous presence in the capital that it is easy to forget how radical an idea it was. The network not only gave citizens thousands of miles away their first real-time, unfiltered look at how government works; it also upended the balance of power in the marble corridors of Capitol Hill.

“Once junior members can acquire notoriety, the ability of older members to coerce them goes down dramatically,” says Newt Gingrich, who arrived in the House chamber as a freshman congressman only a couple of months before C-SPAN did.

In that sense, C-SPAN was a political ancestor of social media and the megaphone it has given to newcomers such as Rep. Alexandria Ocasio-Cortez (D-N.Y.). No longer did lawmakers have to spend decades working their way up the ranks before they had any real voice or influence.

Gingrich was one of the earliest to discern the power and reach of the new channel. It helped launch him to the speaker’s chair and Republicans into the majority for the first time in four decades.

He made himself the star of C-SPAN’s late show, railing after the close of legislative business to a growing fan base of conservatives across the country. By 1984, Gingrich had become such an irritant to those in power that Speaker Tip O’Neill furiously ordered the cameras to pan out and reveal that Gingrich and his backup band of backbenchers were speaking for hours on end to an empty chamber. They kept going anyway.

Nor was the flamethrower from Georgia alone in seeing the network’s potential to put a political career on fast-forward. The very first House member to step into C-SPAN’s unblinking gaze on its 1979 opening day was a 30-year-old Tennessee Democrat named Al Gore — who, as it happened, had written his senior thesis at Harvard on how TV transformed the presidency.

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“Television will change this institution, Mr. Speaker, just as it has changed the executive branch,” Gore said.

That was precisely what Sam Rayburn had feared, when the then-speaker banned the cameras back in the 1950s. Rayburn preferred to have as little contact as possible with journalists, and thought the best kind of House member was one who kept his mouth shut and bided his time in the seniority system.

It did not take long before O’Neill was telling colleagues they had “made a terrible mistake.” The May 1979 budget debate took twice as long as usual, he said, because House members were showboating for the cameras. “Some members now rush back to their offices to see themselves on their new videotape machines,” Newsweek reported.

C-SPAN was the brainchild of Brian Lamb, then the Washington bureau chief of Cablevision magazine, who had been advocating for the burgeoning cable industry to offer more public affairs programming. When he discovered in 1977 that the House was seriously considering the idea of broadcasting its proceedings, Lamb talked the cable operators into setting aside a channel for them.

It took a couple of years to work out the arrangements. House leaders resisted Lamb’s entreaties to install C-SPAN’s own cameras in its sanctum; then, as now, the cameras in the chamber belong to and are controlled by Congress.

As it launched, there was plenty of resistance and skepticism. Older House members worried their constituents would see the unseemly arm-twisting that went on — and that some of them occasionally took naps in the chamber.

Others predicted C-SPAN would have no audience. “House debates are usually so boring and confusing, it’s going to take a very strange person to watch this stuff for any length of time,” political scientist Norman Ornstein told the Los Angeles Times.

It turned out there were such people. In C-SPAN’s early years, a group of Iowa women formed a club called “Watchdogs of Congress,” which met every day around a television. A viewer in Lubbock, Tex., was so addicted that when her cable system dropped C-SPAN, she bought a $2,000 earth-station antenna to get it; the Lubbock city council ordered its cable company to reinstate the channel.

One day in 1983, Lamb was hosting one of C-SPAN’s call-in shows and got a frantic message from his producer to pick up the line on which a caller from Washington was holding. (Lamb usually gave priority to long-distance calls, because they cost money back then.)

After a pause, a woman’s voice came on the air. “Hello, is this Mr. Brian Lamb?” she asked. “Would you hold one moment, please, for the president?”

The caller was indeed Ronald Reagan, who had been watching from his study in the White House, where C-SPAN played on Channel 10. And he had a few things he wanted to get off his chest.

After the House started broadcasting, it would be another seven years before the stodgy Senate would allow cameras in. One of the last holdouts was Minority Leader Robert C. Byrd, who changed his mind after making a visit home to West Virginia and being mistaken for another politician with a shock of white hair. He realized O’Neill had become far more famous than he, thanks in no small part to C-SPAN.

“The Senate is fast becoming the invisible half of Congress,” groused Byrd, who would later become a fixture on C-SPAN2, subjecting its viewers to 100 speeches on the history of the Senate.

When C-SPAN began broadcasting the Senate on June 2, 1986, one of the first to take the floor was — yes, again — Al Gore. Sen. John Glenn (D-Ohio), the former astronaut, comically applied makeup to the top of his balding head, as he declared, “Personally, of course, I plan to do nothing different.” Then he asked viewers in Ohio whether they liked him better in a red tie or a blue one.

But as the novelty wore off, it became more and more apparent what a treasure C-SPAN turned out to be.

The network, which can now be seen in more than 90 million households, still gives us daily proceedings from the House and Senate chambers. It also lets us hear important issues explored in committee rooms, helps us size up candidates on the campaign trail, engages us with book authors and saves a seat for us at think-tank roundtables. It challenges us to think for ourselves, without the clatter of punditry.

So happy birthday, C-SPAN. We need you more than ever.

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