National security, or national defense, is the security and defense of a sovereign state, including its citizens, economy, and institutions, which is regarded as a duty of government. Originally conceived as protection against military attack, national security is widely understood to include also non-military dimensions, including the security from terrorism, minimization of crime, economic security, energy security, environmental security, food security, and cyber-security.

Similarly, national security risks include, in addition to the actions of other nation-states, actions by violent non-state actors, narcotic cartels, and multinational corporations, and also the effects of natural disasters.

Elements of national security include:

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  • Physical security
  • Infrastructure security
  • Computer security
  • Political security
  • Economic security
  • Security of energy and natural resources

Regional Entities

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