There should be no emotional content attached to any new technology. It's how you use it that makes it good or bad. Inevitable? Something like what we call VoIP today is inevitable, but the actual implementation may change drastically in the future. Like a fusion of cell and VoIP phone or even something that's not on the radar yet.
This is a very good point, and I think that this is where we (and regulators) are heading. To the best of my knowledge it's not in the immediate future though.
Yes, but survivability was the underlying principal that Internet was built on, so I don't see it as a disadvantage.
New technology itself isn't good or bad. It's down to how it is used.
Disruptive technology is nothing new. IP is reducing traditional telephony to a subservice, while adding many new services for the end-user. Just like digital-camera's are putting the old photo-developers out of business, or refridgerators doing the same for ice-distributors to use an older example.
Exactly what happens in the transition-phase is too early to tell. POTS-services are likely to exist alongside IP-networks for a long time. VoIP-gateways may even be installed in local-exchanges at some point to cater for POTS-users who refuse to get an internet-connection.
Possibly, but no more than your single POTS-line is today. You may even get redundancy by connecting to multiple suppliers. Telco;s and cable-co;s even have separate infrastructures in many places.
Not if we don't make it that way. The original design of the Internet was to be a type of network that could survive a nuclear war. That's why ARPA and the DOD funded its development.
The DNS servers and other critical infrastructure needs to be separated carefully, and I think this is being done now. The basic root servers of the Internet are, if I'm not mistaken, located on all 6 regularly populated continents. (Antartica has less than 1,000 people living there, it's not a serious location and it's probably not a good place to put servers you might have to go out and do maintenance on. :) )
I understand that during the Gulf War back in 1990, despite saturation bombing, the coalition forces were unable to shut down Iraq's communications networks used for command and control of war operations. They used TCP/IP, the networking protocol of the Internet, and thus we found out that the system really would survive even military bombardment.
I think if the network is still in place, IP telephony will work.