I'm thinking the only people who see it as a problem as far as food growth and such are the ones who are currently growing the food, whatever. The way I see it is someday the great basin of the US might not be a major world food supplier, but maybe death valley or the Sahara, or even Siberia could be that next spot. Still doesn't bother me. We're still here and will continue to be if we adapt. I just don't see any reason to be in a huge rush about it. Time will tell what needs to be done.
Oh and we can start be revoking all welfare programs and letting the less capable fall to natural selection. If we don't we'll basically doom our ourselves to a much worse situation then could be.