Interesting. An excellent example of how fear - based thinking can justify racism and sociopathy even when the underlying scientific principles are otherwise rationally understood (although r-k is somewhat dated theory).
Question: besides disease and natural disasters, what has been the most destructive force affecting humanity throughout history? War, of course. Is it genuinely beneficial for humanity to keep destroying itself and its resources for the sake of genetic evolution when our best path to advancement lies with technology?
Anyway, you make many gross assumptions and inaccuracies. The people in '19 kids and counting' aren't liberals. Those professional couples who have 1 or 2 kids later in life usually aren't conservatives.
You might want to reconsider your position based on the observable facts and not on ideology. What people say they believe and what they actually do are usually not the same. But it is actions, not beliefs, that will determine who will be predator or prey.