It's not so much just the critical utilities and services we have to worry about. If companies (and the government) are smart they'll just have static IP's in case this happens. It'll just be a minor inconvenience right? NO! Many huge corporations rely on the ease of DNS for their customers to find their goods and services online. Sure, if everyone had a text file (a really huge one) of every address and all machines used static IP's then it'd be no problem, assuming everyone that uses a computer knows how to input the correct data. Since this cause a major loss of money on the part of major companies I believe it would be in the intrest of the Department of Defense to protect its country's (and pretty much the worlds) number one source of economic income. Remember, the Internet is a several billion dollar industry.