No doubt I need to be educated about these issues but my initial reaction to this is that calling a nation blind, mute, deaf, and dumb is not an insult to those who are physically or mentally disabled (who presumably would choose to see, speak, hear, and think if they had the choice), but is a insult to those who can see, speak, hear, and think, but choose not to.
If there there's an implicit negative cast to language that describes disabilities, surely that is a result of the fact that disabilities are disabling. You can fight for the civil rights of people who are disabled; you can point out that the disabled are further punished with loss of access to social space, functions, work, play, but I do not see how you can argue against the real loss that accompanies a disability...no matter how supportive a social group is of its disabled members.
If this were not the case, on what basis would a worker who became disabled at work be able to claim compensation for injury? If this were not the case, why do we sit white-knuckled at home when the teenager heads out with the car at night? Do we say to ourselves "Oh, it doesn't matter if the car flips over and he winds up in a wheelchair because think of the rich spiritual life he'll have as a result"? We don't say that. We accept it if it happens, but we don't wish for it and we are not indifferent to the outcome.
I was disfigured for the first fifteen years of my life as a result of putting a live wire (220 volts) in my mouth when I was a year old. I was treated as a freak by children in three different countries (we moved around a lot) and I learned a lot from that. But there are other ways to learn or understand such things. There's always the emphatic imagination; that works too. All in all, given a choice between those first fifteen years of misery and a normal childhood, I would have preferred a normal childhood. At any rate, if someone were to call our fearless leader a moron, I would not interpret this to be a judgement of anyone else but the fearless leader.
We all wish to be whole--in every way there is to be whole. I don't see how we can have a language that is unfaithful to that wish and I don't see how the application of a disability metaphor to those that actually have choice over their blindness or silence can be interpreted as an insult to those that don't.
Joanna