"Crying 'Overpopulation!' is just another means of shifting blame from the rich to the poor." -George Monbiot
The blame lies on Consumptionism (a belief that life can be purchased or taken and consumed-a.k.a. "colonialism"). Simple GDP charts and energy use charts show that it really is a matter of competitive consumption, and there are clear winners and losers, bullies and victims. Saying "We're all in this together!" is a deflection from actualizing the need and changes that are necessary in the rich countries with power.
P.S. Hansen's predictions are already here, so I don't know why I bother. Habit, I guess. Procrastination mostly. There are plenty of specific things I need to do to prepare, and I'm just avoiding my own responsibilities to bitch at you.