Well, shovels that can do real accidental damage (yes, they're called 'backhoes') are actually licensed. So your example is quite good, in fact.
You have to have a special license to operate a backhoe (at least in my country) and you also have to get a work permit to dig at a public territory.
Phones are like backhoes - they have real potential to cause disruptions in public networks and so they are regulated. It's just that regulation framework for mobile phones is quite well designed so it's essentially invisible for end-users.
>at some point you need to hold people responsible for doing the disruption (and account for true accidents) rather than trying to outlaw every possible means of disruption.
Let me quote the GPL for you:
>IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
Do you agree as a GSM stack developer to be liable for disruptions (up to and including loss of life) caused by the code you distribute? If the answer is 'yes' then how this liability is going to be enforced?
IMO, the answer to this problem should lie in well-defined interfaces (hardware and software) between radiomodems and the rest of the device.