How does that make him an asshole? He didn't say he wants children to starve, he said "you shouldn't be having children if you can't feed them." That's good advice, and it would result in
less starvation. Our society is duly judgmental when it comes to more explicit forms of child abuse, but somehow parents who give their children shitty lives by having too many of them that they can't afford get a free pass. If it's the men who are forcing the women to get pregnant all the time, then blame the fathers and the screwed up culture they've created.
To imply that Africans are not at all to blame for the current state of Africa is quite a stretch. It's like in that book Freakanomics where they show that the big drop in crime in the 90's was the delayed result of abortion being legalized in the 70's. It proved a correlation between unwanted children and crime/poverty, which I'd imagine is even more true in a place like Africa. In the end, the solution was less children.
I don't know if Mustang is an asshole or not, and I don't think that Santorum would be a good president, but it seems like people are having kind of knee-jerk reactions and looking to blow things out of proportion.
I wholeheartedly support this advice for the people of Africa.