Elmo
What S41 says is sort of valid - the carriers are trying to be funded out of the Defence Budget not out of a broader government budget. With MOD funding as it is (i.e. several times overspent) were any military programme cancelled there wouldn't be anything "left over" it would just mean the defecit between what we would like/need and what we can afford would be smaller and other programmes would survive the salami slicing or not need to be delayed. This is made worse where we have cancellation clauses that don't work in the MOD favour (i.e Typhoon and I'm sure (but not certain) the Carriers). Bottom line is we are writing cheques that should be bounced and when you sort the programmes in cost (high to low) the carriers sit at the top. And that makes them a seemingly easy target!
Personally I think we are too late to do much about the Carriers other than reduce to 1 (i.e QEII) and take risk we won't need the second during the five-yearly scheduled refit. As S41 points out though it would need a radical overhaul of Defence tasks etc.