You still don't get it (in my opinion)
At the time of Apollo, Mars was thought to be like the Earth.
With Mariner 4, that illusion came to an end, as did a large part of public support for manned spaceflght.
After Mariner 4, it was simply running a race with the Soveit Union, and once that race was done,
that was it.
Especially given the costs of the Vietnam War, Nixon's mishandling of the economy, and the continuing
Israeli-Palestinian conflict.
The only driver for manned spaceflight right now is CAPS in my opinion that is why whoever builds it
will assume leadership in space.
E.P. Grondine
Man and Impact in the Americas