As several of my colleagues noted yesterday, the Supreme Court handed down its landmark decision in Citizens United v. FEC. While I regarded the decision as a victory for free speech, a large number of folks on the left — many of whom support free speech in other contexts — were aghast at the decision, arguing that it would vastly enhance the influence of large corporations in the political process.

Part of my disagreement with these guys is that I’m just a free speech zealot. The First Amendment says “Congress shall make no law … abridging the freedom of speech,” and I don’t see how that language can be squared with a statute that limits the distribution of a political documentary. The best you can say, I think, is that limiting corporate influence is a “compelling state interest” sufficient to overcome the First Amendment’s ban on speech abridgment, but that’s just another way of saying that you don’t care about free speech very much.

Second, I think it’s important to remember that “corporations” encompass much more than large, for-profit businesses. They also include a wide variety of non-profit and advocacy groups, including the ACLU, the NRA, and NARAL, that are, by any reasonable definition, grassroots organizations advocating the views of large numbers of voters. Indeed, as the ACLU pointed out in its amicus brief, the Bipartisan Campaign Reform Act (BCRA) prohibited the ACLU from running ads criticizing members of Congress who voted for the awful FISA Amendments Act of 2008. Even if you think it’s appropriate for Congress to regulate the speech of Exxon-Mobil and Pfizer, I think it’s awfully hard to square the First Amendment with a law that limits the ability of NARAL or the NRA to advocate for its members’ views.

But more fundamentally, I don’t buy the idea that limiting corruption is a state interest sufficiently compelling to overcome the First Amendment interest in free speech. I think supporters of BCRA misunderstand how corporations wield influence and dramatically overestimate the power of television advertisements. It’s true, of course, that a corporation prepared to spend $1 million on ads criticizing a particular legislator will get that legislator’s attention. But there’s nothing unique about this. It can also get his attention by hiring a lobbying firm that employs a former staffer. It can get his attention by arranging $100,000 in bundled contributions from executives, clients, and friends of the company. It can get his attention by creating astroturf organizations. And there are probably lots of other mechanisms I haven’t thought of.

The key difference between independent expenditures and the other mechanisms is that independent expenditures are the most open and transparent. To run an effective “issue ad,” a corporation has to make an argument that is persuasive to voters. I don’t want to sugar coat the situation; sometimes independent expenditures finance ads that are sleazy and misleading. But given a choice between corporations spending their money on ads about how Senator Smith hates America or spending their money on K Street, I’ll take the ads, because at least voters still get the final decision.

Moreover, I think we’re moving toward a world in which traditional high-dollar advertising campaigns will become increasingly ineffective. One smart liberal compares the post-Citizens United world to a debate in which “you get 10 seconds to make your case. I’ll take an hour.” This description of the world had a certain plausibility when most people got their news from newspapers and television — media characterized by severe, technologically imposed bottlenecks. These bottlenecks meant that those willing to spend more money could get a significantly bigger soapbox.

This is a lot less true online where users have practically unlimited choices. The web is littered with lavishly funded corporate propaganda that gets a fraction of the traffic of grassroots blogs like Boing Boing. When people have lots of choices, they aren’t likely to stick around very long at a site that dishes up corporate talking points. So while deep pockets will always be an asset in politics, they won’t give 21st century corporations the huge advantages they gave to 20th century corporations.

So I’m not thrilled at the idea of Fortune 500 companies spending a ton of money on bogus “issue ads.” But I think the dangers of such ads are frequently exaggerated. I’m far more worried about preserving the right of organizations like the ACLU to spread their message. And I don’t see any plausible way to stop the former without seriously restricting the latter. So I’m glad to see the Supreme Court take the words of the First Amendment — “Congress shall make no law” — literally.