Well yes, the whole point of the 4th amendment is so that we can "trust" (in the sense of feeling comfortable with) the government as a whole when it comes to searches because of the requirement for a warrant. In other words, the government has "access" in the technical sense of the word (the police can technically break into your house any time they want), but the requirement for a warrant is supposed to prevent them from misusing that access (they'll get in legal trouble if they break into your house without a warrant).

I wasn't suggesting entitlement so much as practicality. Up until recently, the distinction you're talking about didn't really exist. A warrant might not give police an "entitlement" to something in your house, but there wasn't really a lot you could do stop them from getting it. The best you could do is hide it which isn't very practical in a lot of situations.

But with an encrypted document, suddenly you have new protections. As you suggest, a warrant does the police no good because you also have the right (under the 5th amendment) not to tell them how to access it. Unlike a safe, forcing open an encrypted file might turn out to be impossible. Now you have a technical protection against searches that goes way beyond the legal one found in the 4th amendment.

Again, I'm not saying this is a bad thing, but I think it's an interesting way to look at it and at least one of the points I saw in the article. Technology is less a means to ensure 4th amendment rights and more a means to go beyond them...for both good and bad reasons.