[Modernman]

Societies are either expansive and limited by their environment/conditions/emigration or they are collapsing and supported by immigration.

Other than paying for welfare programs, what reason is there to grow the American population? Certainly, we should be aiming for at least replacement levels. If our native birth rate is lower than replacement level, we can make up the difference with sensible immigration policies.

However, I see no reason to grow the American population to, say, 500 million.

[hopespringseternal]

Certainly, we should be aiming for at least replacement levels. If our native birth rate is lower than replacement level, we can make up the difference with sensible immigration policies.

Two things that will never happen:
1) Birth rates will not be at replacement levels.
2) Our politics will never allow sensible or even sane immigration policies.