>How long did the SR-71 take to make it into service? How long did the F-22 or F-35 take?

>None of those answers have anything to do with the other.

There's a pretty direct correlation between number of stakeholders who need to not object and procurement time.

One trick pony spy plane go fast took no time at all.

F15 but stealth took years

F35 cluster fuck took decades.