Science vs diseases

Science vs diseases

Do you think one day Science will find a cure for all diseases?
One of the many questions I have been thinking about these past days. in case you are wondering why I ponder over such serious issues all of a sudden, it is because "Science and human progress" is one of the many subjects on which I may be asked to write an essay or make an argumentation about in my forthcoming French examination - Fourthcoming is more like it as the exams are on the 4th.
As my head was getting more and more muddled with issues relating to culture, society, science and economics I got a brilliant idea - why not ask the question here and take your views and use it all in my essay!
So here I ask the first of the questions:
"Do you think one day Science will find a cure for all diseases?"
And here's what I think about it:
While it is a desired goal to alleviate humanity of all suffering from diseases, what happens if all diseases are curable and humanity becomes immortal? Would the earth be able to sustain the population levels and would we have enough resources to go around? Would we then have to impose restraints on new babies being born? Wouldn't Earth then become a planet of very old people or would a body free from all diseases remain young forever?
On another level, when there is no death to fear, would we be motivated to make the best use of this life? Or would a kind of inertia set in as we know we have "forever' to do everything. What happens if we get bored with living forever? There is no escape route right - no hope of dying! So would we have schemes like a person could opt for death so that a new baby can be sanctioned to the family - someone would be allowed to bear a child or clone someone?
Bizarre right? I guess nature knows its job best and that's why we come with a short life span - so that the population is regulated and it is recomposed every now and then with new life.
While it is necessary to find a cure for killer diseases like AIDS and Cancer that take away so many young people, perhaps it would be a good idea not to find a cure for at least the ones that affect us in old age.
Death is not such a bad idea when you are 100. What do you think?

P.s: A friend pointed out that disease is not the only cause of death. What about accidents and murders and natural calamities? I agree. but aren't these just a small proportion compared to deaths due to diseases and old age? As for the natural attrition of the body, we seem to be waging a war there too with anti-ageing solutions.(Like they say today's 60 is yesterday's 40 and so on...) So isn't disease still a major cause of death?
Or we would then kill each other waging war and fighting for the scarce resources?
And if we are anyway going to kill each other then why even bother to prolong life with finding cures for all diseases?