>"So if you get a warrant to search your hard drive for something, you are compelled to give them the password just like you are compelled to let them into your house if they have a warrant to search for something like drugs or guns or counterfeit plush toys."
You might also be missing something about TrueCrypt: plausible deniability. You can have different passphrases that unlock different things. You could provide them with a passphrase the only unlocks innocent documents when really you have CP stored using a DIFFERENT pass phrase -- any this would stand up to any cryptographical analysis -- they simply cannot PROVE that the CP exists or even that more encrypted data exists.
The analogy to a key isn't quite valid here; it's more like the doors in that hallway in the matrix. If you use key A in the door, you will get content A. However, you can use a different key, open the door, and it'll go somewhere else entirely. Also, if you rip the door off the wall, there is just the wall behind it. Crazy stuff, that.
You might also be missing something about TrueCrypt: plausible deniability. You can have different passphrases that unlock different things. You could provide them with a passphrase the only unlocks innocent documents when really you have CP stored using a DIFFERENT pass phrase -- any this would stand up to any cryptographical analysis -- they simply cannot PROVE that the CP exists or even that more encrypted data exists.
The analogy to a key isn't quite valid here; it's more like the doors in that hallway in the matrix. If you use key A in the door, you will get content A. However, you can use a different key, open the door, and it'll go somewhere else entirely. Also, if you rip the door off the wall, there is just the wall behind it. Crazy stuff, that.