Another wave of survivalism began after the September 11, 2001, attacks and subsequent bombings in Bali, Madrid, and London. This resurgence of interest in survivalism appears to be as strong as the 1970s era focus on the topic. The fear of war, avian influenza, energy shortages, environmental disasters, and global climate change, coupled with economic uncertainty and the apparent vulnerability of humanity after the 2004 Indian Ocean earthquake and tsunami and Hurricane Katrina, have increased interest in survivalism topics.