Either way. The B-24 was far more versatile than the B-17. Had America wanted to trying something like the Dambusters raid it would have been B-24s doing it.
I don't think you can honestly say the Americans would have never come up with anything that would have worked. We never considered a raid on the dams and if we had I am reasonably sure we could have made something work. If not, we could've just nuked em.
That was a (mostly) sarcastic comment and was intended to remind Lanc that America had some skill at weapons development.
Part of the reason only one man came up with the idea was that only one man was looking for it. If America had had an interested in attacking the dams, an appropriate weapon would have been developed.