What's stopping this from happening again? Well, if you ask Donnie Rumsfeld, the answer seems to be "get the camera phones out of Iraq" [link to boingboing_net summary]. That's not closing the barn door after the horses are gone. That's burning down the barn because we don't want any more escapes from it. What our modern empire could really use is a healthy dose of Self-Reflective Moment: looking very hard at ourselves from the point of view of the rest of the world. We are bastards. Utter and total bastards.
We Americans won't get that Self-Reflective Moment any time soon, at least not at a national-consciousness kind of level. I can only struggle to see that we keep getting our chances to do so, for example by lobbying for IRV, which the Australians and Irish, among others, have pulled off, and by making sure that voting still matters. At this point, I'm worried about the damage our Feckless Leader is doing, and thinking about firewalls to limit the damage to the whole democratic apparatus.
Xeni at boingboing_net points out a New York Times article that discusses the latest good idea in a long chain of tweaks to the source code of political democracy: opening source code for voting machines to the general public. Great quotable moment (italics mine):
But if our code were open, wouldn't cyberterrorists or other outlaws be able to locate flaws and possibly rig an election? Well, theoretically -- except that it's highly unlikely that they could spot an error that escaped thousands and thousands of scrutineers. Indeed, it may be far easier to infiltrate [or buy --trochee] a private-sector company and tamper with its software....Resting the safety of the world's most powerful alleged democracy on a single point-of-failure in a small tech company is a terribly bad idea. Call us freaks or nutty if you like. (I draw the line at "libertarian", myself, unless you qualify it with "civil".) But it's fiddling while Rome burns to pretend it wouldn't matter.
Open-source enthusiasts, by contrast, are precisely the sort of people you'd like to see inspecting the voting code; they're often libertarian freaks, nuttily suspicious of centralized power, and they'd scream to the high heavens if they found anything wrong.
Simply put, source code is only the beginning. The strength of written law -- such as it is -- rests in there being one law for all the people. Though that's rarely how it works in practice, making the law available publicly is an attempt in this direction (though the language is too obscure for most people). The same could be said for source code. While we're at it, why not make the tax code available in government-sanctioned source form, rather than allowing the TurboTax people etc to reap profits from their reverse-engineering of the evil stickiness of the English language tax codebase?
More openness in government. More paranoid [civil] libertarians reviewing the practices. This is the strength of public debate.