The United States currently faces a dynamic, flexible, and very pragmatic adversary. Due to the unconventional nature of the terrorist threat and the asymmetrical tactics demonstrated both at home and abroad by our enemies, we can no longer expect the protection formerly provided by the oceans bordering our coasts to serve as an effective deterrent to attack. The attacks of September 11, 2001, and other events demonstrated that an act of terrorism can cause worldwide infrastructure asset disruption. In the past decade, hurricanes or other violent storms have also revealed that our infrastructure assets are at risk from destruction, degradation, or disruption by natural events. Given scarce resources, this Strategy’s objectives must be balanced against other priorities outlined in the National Defense Strategy.