Twitter has proven once and for all that sometimes less is more, that David can beat Goliath, and maybe even that the bigger they are, the harder they fall.Twitter has accomplished all this by being able to slip through the bandwidth bottleneck fashioned by Iranian mullahs intent on keeping news of dissent corked up in their country.

Twitter has played such a crucial role in helping Iranians communicate amongst each other and with the outside world that the U.S. State Department has asked Twitter to postpone maintenance work that would have brought the service down temporarily.

It has even inspired some lamebrains to claim that the Tweets heard 'round the world are actually the work of the Israeli secret service, an idea thoroughly debunked by Chris Anderson of TED, but worthy of mention only because it illustrates the proportions that this social phenomenon has taken.

Because the service is so light, it can even be accessed using a dial-up connection -- in other words, short of shutting down the country's entire communications infrastructure, the Iranian government cannot filter out all the dissident Tweets.

Harvard's Jonathan Zittrain explains why Twitter is capable of delivering what other services cannot:

This isn't to say that Iranian Tweeters aren't facing monumental challenges, as the Guardian reports:

Fortunately, Iranian dissidents are at least as capable of handling the technology as anyone in the West, as illustrated by this series of Tweets aggregated by Andrew Sullivan:

And:

Nor do they lack in courage (not to mention fatalistic humor):

Clay Shirky provides a great explanation of how cell phones and Twitter can "make history," and history is indeed being made right now.

But what's most appealing about Twitter is the idea that a very small thing with an innocuous name symbolizing the chirping of a sparrow can be wielded by a small group of people to outwit and, perhaps, defeat the weaponized forces of oppression.