Individually we aren't. But collectively we've shown, time and again, just how stupid we are. And we'll never be able to reach a consensus on a new economic model because of it.
I can't speak for people in other nations (I'm an American) even though I suspect I know how they would react. But I have a pretty good idea of how Americans will behave. Many of them will scream "socialist" and want nothing to do with it. Many others will complain about having to pay for it, even though they themselves are already beyond broke and use more resources than they actually contribute back. Some will never want to relinquish the (illusion of) control they believe they have over the world. We can't reach a consensus amongst ourselves, let alone with people who have different political philosophies. In other words, good luck getting us to agree with the Chinese or the Russians.
If there's going to be an intelligent solution found it will have to be found by the people with the rapidly growing populations. The future really is up to the Chinese, Indians and Africans. Don't blow it guys.
Of course it's just as likely some pointless war will greatly reduce the population pressure before the century is out...