Savings numbers aside, I think the bigger issue at hand is do we really need this airplane?
I'll be the first to tell you it's cool as hell. I always thought the Harrier was one of the coolest planes, but that thing is getting along in age-and this would be its direct replacement. It's all got very cool technology that should be implemented asap.
However, why do we need a plane that hovers? Besides take off from roads, small boats and FOBs, I fail to see a tremendous need we have for this plane. I have a hard time convincing myself that we needed the F-22, but that's a whole other issue and it's already in service anyway. But the F-35 doesn't deploy troops, and it doesn't hover for flight-just for take-off and landing. And for what? To save fuel in logistics? At the cost of hundreds of billions of dollars.
The USAF plans to use it as a replacement for the F-16. The USN, the F/A-18, and the Marines the AV-8B. The AF already has the F-22, which is not only an air superiority fighter (something we don't really need), but will end up serving as a multirole fighter. That makes it a good replacement for the F-15 and the F-16. The Super Hornet only came out 15 years ago. Make more of those. The Marines, I'll admit, do need a replacement for the aging Harrier. It's a workhorse of their branch, and only the F-35 can replace it.
But you know who really needs the F-35? The British. The Royal Navy doesn't operate aircraft carriers as large as we do, nor do any of the other countries that are helping us develop this aircraft. So their need for a plane able to take off on their significantly smaller carriers is much greater than ours. So why are we footing such a large bill for it?
I'll tell you the problem. Everyone knows that they can't possibly keep up with our defense spending, and realize that we can take care of their military needs, so they cut back. We have to increase our defense spending to make up for the difference between we keep our presense in everyone's back yard. We help out more, they spend less. Circular reasoning works because circular reasoning works...
We can't govern the world unless we tax the world.