Are file permissions in files on external devices silly?

[Mario Vukelic]

On Fri, 2008-11-21 at 16:19 +0000, Andrew Sayers wrote:
> To address the actual point, security of files on removable media can
> only be handled at the hardware level, by making sure bad people don't
> steal your disks.  Bad guys can be assumed to have root access to at
> least one box that they can plug a drive into, so complex permissions
> systems on removable media serve only to frustrate ordinary users.

I have to disagree here. I have several USB disks attached to my
computer, and while I agree that this provides no security against an
attack, it does provide protection against user errors, just as it does
on internal disks. A disk being external does not preclude that several
users access it and want protection from the other guy unintentionally
deleting their files.