Why today's Web blackouts are working

There's no guarantee that the decision by Wikipedia and others to go dark in protest of SOPA and PIPA will stymie the legislation. But the blackouts are dominating media -- and that's the whole idea.

FORTUNE -- I just looked at a Google cache version of a Wikipedia page. It's easy to do that, so today's blackout of the online encyclopedia, in protest of proposed anti-piracy legislation, isn't totally effective in blocking access to the site. But it is effective in making people aware of the legislation and in spurring further protest, which is the whole point.

A week ago, the House's proposed Stop Online Privacy Act (SOPA) and the Senate's proposed Protect IP Act (PIPA) were getting relatively light attention. Today, they're dominating both the traditional and social media. Nothing significant has happened with the legislation itself -- it's simply the blackouts. Wikipedia is just one of a many sites that have gone dark today.

Predictably, the campaign has spurred cynical retorts. "SOPA supporters wont be able to access Moveon.org -- that'll show em," tweeted Rolling Stone political reporter Tim Dickinson. He is far from alone in missing the point entirely. The idea isn't to punish supporters of the bills; it's to inform people of what's in those bills by drawing attention to them. (Fortune's parent company, Time Warner, is a supporter of the legislation.)

This happens whenever there are online protests or awareness campaigns. Would-be world-wise types are sure to weigh in whenever an awareness meme spreads on Facebook, for example. In 2010, people replaced their profile photos with images of their favorite cartoon kids in a child abuse awareness campaign. "Oh, sure," came the above-it-all responses, "posting cartoon pictures on Facebook will definitely end child abuse."

But of course, nobody said it would, just like nobody is saying that today's blackouts by themselves will kill SOPA/PIPA (though, given the reaction today, it really could turn out to be the thing that turns the tide -- because now many, many more people know what's in the bills. And now it appears that some congressional minds are being changed.). If even just a handful of people donated to anti-child-abuse charities, or were simply made more aware of the problem, then the Facebook meme worked.

It could be that Internet-based awareness movements draw criticism simply because they're Internet-based. Since the people taking part in them are sitting at their desks as opposed to marching in the streets, that somehow makes the whole thing seem less serious.  But if the idea is to inform people, the Internet is the most powerful tool available. The point isn't to put oneself through as much hardship as possible -- the point is to spread information.

Twitter CEO Dick Costolo was asked why his site didn't shut down today. "[C]losing a global business in reaction to single-issue national politics is foolish," he said. He's right, it would have been foolish for Twitter to do so (just for one thing, Twitter is the main clearinghouse for real-time news and information on the issue), but that doesn't mean it's wrong for others. "Not shutting down a service doesn't equal not taking the proper stance on an issue," he continued. "We've been very clear about our stance."

Twitter has done nothing wrong by opting to stay live. But it's also true that if Twitter (or Facebook or Google) had gone dark, it would have been an even bigger news story today. It probably would also have alienated a lot of the people that the movement is trying to attract. But it would have gotten a lot more attention than "Twitter opposes SOPA."