Nowadays, USA cannot put a rover on the moon in less than 20 years.
That's probably because we're too busy putting all kinds of rovers on Mars, the last one of which was as big as a car and was placed there by a skycrane that was never used before and could have malfunctioned in a million different ways, and yet it was completely successful.
USA put men on the moon ~50 years ago and now, it can't put a rover on the moon because of an already completed transport and landing on Mars (which will have no follow-up)?
No. It cannot put a rover on the moon because it does not have the necessary hardware and it needs 20 years to create it. Because, after said lunar landings, it not only stopped going forward, it went in full reverse.
Nowadays, in space related matters, USA is a has been, limited to orbital space, comforting itself with memories of its golden age.