The odds of a 'zombie attack' are growing very year. Human population growth and environmental degradation in the global south are making life ever more difficult, exacerbated by climate change which is already affecting food production in the tropics. The Middle East will continue to melt down, and Africa's current population of one billion hungry people is on a trajectory to reach 4-6 billion by the end of this century. Those desperate people will continue to head for Europe in increasing numbers and a wide scale natural or economic disaster would turn the northward flow from Mexico and Central America into a flood. It ain't gonna be pretty.