[episteme]

If torturing and kidnap are on the table, how does this help? They can torture you to give them the keys just like a password.

[nailer]

He can’t give the attackers the customer keys or any other data. But yes as another poster says downtown the attackers may not actually understand that.

[j3th9n]

You might want to study asymetric cryptography.

[bgwalter]

No, you'd better hope that the kidnappers have studied cryptography. If they think they can extract something, they'll go ahead anyway.