Yes, we don't know how to do that, but we don't know how to build hundreds of aircraft carriers per year right now either, yes the US has done the later in WW2 and would probably be able to do it again should it be needed in an existential war.
With a sustained nationwide effort comparable to WW2 we could most likely send a spaceship out if the solar system in ten years or so. But why would anyone do that?
With a sustained nationwide effort comparable to WW2 we could most likely send a spaceship out if the solar system in ten years or so. But why would anyone do that?