War
Someone said that war is the normal state of human affairs and that peace was an interruption. In the dictionary, 'peace' is defined as the period between two wars. Well, what with all the financial trouble facing the world, peace may not last long. Indeed, since the end of the Cold War, sporadic regional conflicts have increased at an alarming rate.
The biggest danger facing us is the way people think WWII got us out of the Great Depression. Think about it - if that is what people believe, they will welcome war. The leaders, that is.
The powers that be are becoming ever more involved in Iraq and Afghanistan. They are prodding Iran, and as of the end of 2009, are poking Yemen. They will use any terror attacks to heighten fear and use that to take more control.