If you need an example, pick the Clipper chip - and even that doesn't _quite_ work out, given how publically that proposal was shot down.
https://en.wikipedia.org/wiki/Thomas_Andrews_Drake#2007_FBI_...
https://en.wikipedia.org/wiki/NSA_warrantless_surveillance_c...
The thing is that they can not bring the result of this warrantless wiretapping into court. But they probably don't want to.
From what I've seen the FBI is a lot more vocal in complaining about the impact of encryption because their mandate involves bringing cases to court so they want a formalized, legitimate way of breaking encryption when they have warrants. They would also love to have the dragnet that the NSA has to know who to watch, and I don't know to what extent they do, but the bigger difference that I see is that the NSA is not interested in launching court battles (any more) whereas that is the primary endgame for the FBI.
The problem of course is that an encryption system which can be broken in a formalized way is open to the possibility of being broken by the wrong people. You can't have your cake and eat it too by having strong encryption that can be broken by the "right" people because there is no way to theoretically describe who the "right" people are. The encryption has to work the same for everyone.
Like all big issues in society there are competing rights; the need for law enforcement bumps up against the freedom of the individual. I believe that we are comfortable enough pushing this balance more heavily towards the freedom of the individual in America that a policy of embracing strong encryption is in the best interests of everyone, but I am aware that I don't have as much knowledge about this issue as some others.
Doing this in a non-obvious way seems much more difficult, but if the NSA did have a weakness to DES, it could very possibly require knowing a secret key.
If they had been given that authority things may have been different.
Lets look at the case where X is regulate the sale of switchblades. The federal government has the authority to regulate the sale (commerce) of switchblade knives between states, the federal government does not have the authority to regulate the sale of a switchblade within a state.
Let's look at the case of guns. Do you really think that Montana could say "you can sell Montana-made machineguns in Montan without satisfying federal law"? (The feds don't much care about switchblades. They care about guns.)
See http://en.wikipedia.org/wiki/Wickard_v._Filburn . In that case, the feds got to regulate even though the wheat in question wasn't sold and never left the farm.
Wickard was 70 years ago, interstate commerce doctrine has evolved a lot in the intervening years. In fact I'm a little surprised that you used it as an example. It has been a while since ConLaw I, but I think Wickard is often used as an example of the height of the broad interpretation of the commerce clause. Are you arguing that there is no limit on the power of the the commerce clause? Or that Wickard is the controlling case? Lopez is one of many cases since Wickard where the Supremes walked back such a broad interpretation of the commerce clause.
When prohibition was passed, the Civil War was still in memory and Congress felt it needed a constitutional amendment to ban ethyl alcohol.
Today, if Congress wants to ban a thing they simply pass a law that puts you in jail for its sale or possession. Simple as that.
Today? They have always done that. Which is why the USC reads as follows:
"Whoever knowingly introduces, or manufactures for introduction, into interstate commerce, or transports or distributes in interstate commerce, any switchblade knife, shall be fined not more than $2,000 or imprisoned not more than five years, or both."
The Supremes haven't overturned Wickard.
Yes, they did decide that the first version of the Gun Free School Zones Act didn't have a commerce nexus, but they seem quite content with the current version, which affects only those guns that have gone interstate.
However, the relevant question is whether the Supremes have ever decided that something sold can be exempt from the federal power to regulate interstate commerce.
Take machine guns. A Montana statute that allows unrestricted sale of machine guns made in Montana clearly affects "commerce" (in Montana at the very least) of guns not made in Montana, aka "interstate guns".
Do you really think that the Supremes would reject that argument? On what basis?
And, if they accept that argument wrt guns, why wouldn't they accept it wrt cantalope?
The United States Constitution is the highest law, and provides for different treatment of foreign and domestic matters, so your statement is obviously false even under the most broad interpretation of "the government".
The President/Executive (closest to what many other countries would consider "the government") is also limited in most matters by the laws passed by Congress, so even assuming domestic regulation of cryptography were Constitutional (and I don't personally believe it would be), if Congress has not passed a law giving the Executive the authority to regulate it, the Executive cannot do so.
The suggestion that policy is justified merely because it subsists upon formal authority is nonsense.