Weeding out corporate espionage is one thing, weeding out espionage with the backing of the government is a completely different thing. About a year and a half a go in my Mercury Rising essay , I wrote that there are virtually no unbreakable codes. In theory, this is true. The encryption code I described in that essay is similar to a one-time pad in that the pseudo randomness can be found in the complex algorithm and in the file used to create it. There are three problems.
True randomness is hard to come by, and any flaw in the randomness can be exploited.
Second, it is unpractical to come up with a new random one-time pad that can be accessed by sender and receiver for each and every message. Third, not only do you have to get the message from sender and receiver, you also have to get the one time pad from sender to receiver, and that ends up being a security risk. Neal Stephenson's latest novel Cryptonomicon describes how each of these flaws can be exploited. Now in getting past Echelon, so that you can have secure live two way phone conversations, you have to use scrambler technology that is far less secure than the one-time pad mentioned above. And the NSA, almost certainly has the resources.