Emergency management has four distinct phases which are applied in order to manage any emergency situation and also to assess and control risks. These four phases are mitigation, preparedness, response, and recovery. All of these phases has its own unique role in managing the risks of terrorism because understanding the threats and mitigate them or to be prepared for these are its main goals. Terrorism is posing as one of the main and dangerous threats to the homeland security and these four phases of risk management because these multiple phases allow the department to understand the risk to its core and take important measures for mitigating those risks.