A big motivation was that developing combat aircraft is stupidly expensive and extremely prone to cost overruns, which then make programs vulnerable to cancellation. So the defense industry and DoD got together to make this project very difficult to cancel. They sold the virtues of cost savings by sharing components, then they staked the future of US and allied air power on this one platform. On top of that they spread the production of the aircraft across FORTY-FIVE states. It is not only the most expensive weapons program in history, it is the most politically engineered.
> But the US can afford specialised aircraft. Betting the house on a jack-of-all-trades means you end up with a master of none. The US should be master of everything, and that means more specialised fighters, bombers, CAS, etc.
Yes, but one of the critical weaknesses of the US military's philosophy is that if it's worth doing, it's worth overdoing. The DoD frequently capitulates to the desire to gold plate weapons systems and change requirements to the point that projects get cancelled. So, the JSF is in a way, a response to that tendency, just the totally wrong one.
> If the A-10 isn't good enough anymore, by all means design a replacement. But don't expect it to also take of vertically and perform air superiority. Everything comes at a trade-off. Having an airframe designed for VTOL and then use it for planes that don't VTOL is just wasteful.
I think the STOVL requirement is key factor that really effed up the JSF program. And that entire requirement is born out of an irrational institutional fear the Marine Corps has about being left without air support that they harbor from WWII.