Preventing and Defending Against Cyber Attacks
"The Nation’s first ever Quadrennial Homeland Security Review (QHSR), delivered to Congress in February 2010, identified “safeguarding and securing cyberspace” as one of the Nation’s five priority homeland security missions.

The Department of Homeland Security (DHS) is responsible for helping Federal Executive Branch civilian departments and agencies secure their unclassified networks (.gov). DHS also works with owners and operators of critical infrastructure and key resources (CIKR)—whether private sector, state, or municipality-owned—to bolster their cybersecurity preparedness, risk assessment and mitigation and incident response capabilities..."