Ken, Really. I hope I've made it clear somewhere in the last 415 pages that, as we say, it depends.
Fascinating. "It depends" has been my position from the moment I began contributing to this thread. I'll leave it at that.
But the F-35 cannot be stealthy and carry a HOBS system
Once again, "it depends". Are AIM-120C5 and C7 HOBS systems?
As for Japan's F3, it will almost certainly be a joint development in much the same way that their F2 was a joint development. But what will it be jointly developed with? The F-35 follow on aircraft? That seems unlikely as according to AvWeek, Japan wants the F3 to enter production when the F2 begins retiring, and the F-35 follow on will almost certainly not meet that timeline. Maybe Japan will join USN's F/A-XX program to replace the Super Hornet? Interestingly, USN thinks that aircraft will be LESS stealthy than F-35. Apparently, USN is much less sold on stealth than USAF.