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Layered Nuclear Defense: Interior Layer

Two officers checking a truck for nuclear material

The interior layer of the Global Nuclear Detection Architecture (GNDA) includes all areas within and up to, but not including, the U.S. border. The interior layer focuses on increasing nuclear detection capabilities across the maritime, air, and land pathways and addressing a wide array of potential threats.

The nuclear detection mission in the interior U.S. is conducted by federal, state, territorial, tribal, and local jurisdictions across potential threat pathways across all domains. These capabilities center on detecting and identifying radiological and nuclear threats that have either been smuggled into or acquired within the U.S.

The interior layer includes consideration of the following:

  • Maritime modes of transportation within the interior layer that include public and private vessels operating on lakes and rivers within the borders of the United States
  • Air modes of transportation within the interior layer that include commercial and general aviation between domestic airports or unofficial landing strips
  • Land modes of transportation within the interior layer that include public and private automobile traffic across the U.S. highway system, regional rail and various types of off-road travel.

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