We are certainly living in exciting times.“Wildlife experts in and around Yellowstone National Park have enough trouble trying to get the public to accept the presence of wolves – carnivores that were extirpated from the area within recent history before being reintroduced two decades ago – and conservationists continue to struggle with the persistent conflict between jaguars and ranchers in South America. Can you imagine the uproar over sabertoothed cats being returned to the western United States or South American grasslands?”
-I don't think this is a feasible way to go, unfortunately. Even with something as seemingly benign as reintroducing the Passenger Pigeon, couldn't there be some large unintended consequences? I would think the most prudent thing to do (aside from not doing it in the first place) would be to have sanctuaries for such endeavors. I could see a thriving tourism economy around this. I would pay money to go see a Saber Toothed Tiger or a Wooly Mammoth. But I don't think I'd like to see either in my back yard.
You know what, it is surprising but I think my opinion is changing on this slightly. For a long time I was a big supporter for de-extinction (except for Neanderthals. However, I don't think we are ready for it in a big way... especially considering many Paleolithic megafauna were adapted to an Ice Age climate. It would be foolish to bring them into our world until we stop climate change. And like you said... no one is going to want a wild saber-toothed cat in their backyard. But you bring up a good point about a tourism economy... if I was a betting man I'd say there will be a Paleolithic Park before 2050.