NYT reveals the backstory on Stuxnet
David Sanger:
The unusually tight collaboration with Israel was driven by two imperatives. Israel’s Unit 8200, a part of its military, had technical expertise that rivaled the N.S.A.’s, and the Israelis had deep intelligence about operations at Natanz that would be vital to making the cyberattack a success.
Without the extensive knowledge the Israelis had acquired about Natanz, and without their ability to get the worm into Natanz, the project would likely not have been possible. That is, the cybermagic depended on an elaborate, expensive and dangerous old-school spying operation. Again, cyberweapons like Stuxnet are not within reach of groups like Al Qaeda or Anonymous. Not even Iran today.

