Today we look back at 2012. In the most expensive election in U.S. history, President Barack Obama defeated Mitt Romney, forcing the Republicans to reconsider their policies, among others, around women and immigrants. While the major party presidential candidates did not take on climate change in any of their debates, it was a year of extreme weather — from the melting of the Arctic to Superstorm Sandy, to the massive typhoon in the Philippines. 2012 will also be remembered for a series of mass shootings: from Aurora, Colorado, to the Sikh temple in Wisconsin, to the Sandy Hook Elementary School in Newtown, Connecticut. The shooting death of the unarmed teenager Trayvon Martin in Florida sparked national protests, after police initially refused to arrest the gunman, George Zimmerman. The U.S. war in Afghanistan entered its 12th year, while Obama continues to expand his secret drone wars.