God bless Josh, for thinking big.  Whether moving certain animals to North America is a good thing for the individual animals may be defensible, but is certainly controversial to those of us interested in animal rights. (I myself am of two minds, or three, or six, or a dozen, on the matter of whether saving species, as opposed to saving individual animals, is just another anthropocentric self-regarding game.)  The whole experiment would be a terrific learning experience for all of us.  But the animals come first.  It sounds remarkably cruel to land African mammals in the Dakotas and expect them to be happy.  Bactrian camels might do fine there.  But lions, cheetahs, elephants will certainly not.

but where will you put those animals?  The U.S. is so grossly overpopulated that wherever they used to live isn't there anymore.

RE the aminal rightser, you've got to be kidding!  Individuals are more important than species?!  I know you people can be illogical, but this takes the cake.

This is a great article by a man with conservation biology ideas and Earth First! sentiments.  I love Josh Donlan's idea, I would love to see megafauna from Asia and Africa roaming the plains and forests of the US.  But that dream makes me sad because I'd like it so much more than the shopping malls, highways, cars, trucks and suburbs that are currently overpopulating the American landscape -- and it isn't going to happen.  It's an idea whose time has gone, very unfortunately.  There are too many people in the US, most of them conditioned to be scared of megafauna and ignorant of the importance of biodiversity.  

When the reality of oil depletion hits, land will be needed to grow food.  That could be soon.  And then it will be too late and too expensive to bring lions and tigers and elephants, etc,. over from Eurasia and Africa.  Maybe after the die off (or die back) of humans, the animals of the Earth (if there are any left) will repopulate North America, but not until then.  That is my regretful opinion.

I also share concern about the trauma of relocating megafauna from far continents.  It's hard enough to successfully do it within North America, as when lynx were relocated from Canada to the Colorado Rockies and most of them starved to death.   It wouldn't be fair or kind to the animals -- too risky.  Better for humans to grow up and accept what a mess we've made of this planet and humbly become ecoliterate in order to survive global warming and oil depletion.  There's no time to lose!