SteveZ, my entire career was in advertising and public relations -- as a writer. The essence of this "computer" ad was to show just how out of touch with today's world, McCain is. And, guess what. In my opinion, he is. And yes, it is targeted to the younger voters. So again, to dissect this ad: it's geared to the younger voter, and to show how out of touch with today's world that John McCain is. This ad does the job superbly.
It has NOTHING to do with disabled veterans! NOTHING! And as far as disabled people using computers and keeping up, do you know who Professor Stephen Hawkings was?
The computer system attached to his wheelchair is operated by Hawking via an infra-red 'blink switch' clipped onto his glasses. By scrunching his right cheek up, he is able to talk, compose speeches and research papers, browse the World Wide Web, and write e-mails. The system also uses radio transmission to provide control over doors in his home and office. His computer was created by an American engineer. He once joked that his computer "had an American accent".
Nice try!