Hurricane Sandy struck the U.S. East Coast in October 2012, leaving about $65 billion of damage in its wake and raising the question of how to mitigate the damage from future storms. It’s a question that arises in the wake of most natural disasters: What steps can society take to protect itself from storms, floods, landslides, earthquakes, tsunamis or volcanic eruptions? But the question itself illustrates the complexity of preparing for natural disasters.