It's not the first space-based observatory, but it's still a _wholly novel_ device, containing instrumentation designed by scientists and engineers in concert to leverage every piece of bleeding edge technology available at the time, and some throughout the process. Everyone of the flagship observatories is moon shot. It's not a mass-produced helicopter or missile. This project in particular is easily one of the wildest feats of science and engineering _ever_ just like Hubble, Cern, and LIGO.
Regarding the bomb, we were trying to end a global conflict, so the comparison couldn't be further off base.