Hal Finney wrote :

However if the system is designed to make it easy when it does become necessary, it will probably be easy to at least occasionally activate the feature accidentally. The result will be the loss of your keys.

For what little it is worth, key zeroization is built into almost all US government crypto gear, usually with prominent switches on the front panel marked "zeroize" for emergencies. And most all of this gear has tamper switches that activate the zeroizing logic when any of the covers of the equipment are removed - and often there is more than one zeroize circuit in a system in case the primary one fails to work. My understanding is that the NSA has rather specific and detailed requirements for this feature in gear being designed for them, and one can certainly see why it would be a requirement in military systems that might have to be quickly rendered useless to an enemy in the moments before capture. So it is hardly a new idea. Dave Emery die@die.com