Yes, and that's smaller than a rounding error in our current $4.7T budget. Hell, the $100B (today's dollars) Apollo program would also be smaller than the rounding error, since it was spread over a decade. The R&D costs on F-35 were almost triple the whole costs of Manhattan project.

Truly, we are easily able to afford projects like Manhattan and Apollo today, it's just we aren't able to pull them off anymore.