HS,
Have you met the term "Force Multiplier"? No E-3/AEW is expensive in pointy jets!!
Take your point, but it is a bit of thin argument to say the least. You could equally well state that no MPA is expensive in long, thin greyline war canoes.
We binned MPAs having operated them without a break since the mid nineteen thirties. The history of AEW in the RAF is whole lot less consistent than that!
Trust me, there ain't no sacred cows no more (well, maybe one...wonder where they will put it if AS gets his way??)