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Maritime Security

Maritime law enforcement and border control are the oldest of the Coast Guard’s numerous responsibilities. They date back to our founding as the Revenue Marine in 1790. The First Congress established the Revenue Marine specifically to patrol our coasts and seaports to frustrate smuggling and enforce the customs laws of the fledgling Republic. Over two centuries later, that early challenge has evolved into a global obligation for the maritime security of our nation. Our maritime law enforcement and border control duties require the interdiction of ships at sea. This core capability provides the foundation upon which today’s broader and more complex maritime security mission set has been built.

As the Nation’s primary maritime law enforcement service, the Coast Guard enforces, or assists in enforcing, federal laws and treaties on waters under U.S. jurisdiction, and other international agreements on the high seas. We possess the civil authority to board any vessel subject to U.S. jurisdiction. Once aboard, we can inspect, search, inquire, and arrest. We wield this broad police power with prudence and restraint primarily to suppress violations of our drug, immigration, and fisheries laws, as well as to secure our nation from terrorist threats.

The Coast Guard is the designated lead agency for maritime drug interdiction under the National Drug Control Strategy and the co-lead agency for air interdiction operations with U.S. Customs and Border Protection. As such, the Coast Guard defends America’s seaward frontier against a torrent of illegal drugs. For more than three decades, our cutters and aircraft have forward deployed off South America and in the drug transit zone. They have intercepted thousands of tons of cocaine, marijuana, and other illegal drugs that otherwise would have found their way to America’s streets.

Coast Guard undocumented migrant interdiction operations are law enforcement missions with an important humanitarian dimension. Migrants often take great risks and endure significant hardships in their attempts to flee their countries and enter the United States. In many cases, migrant vessels interdicted at sea are overloaded and unseaworthy, lack basic safety equipment, and are operated by inexperienced mariners. Many of the undocumented migrant cases we handle actually begin as search and rescue incidents. Once again, this illustrates the interweaving of our roles and missions. Between 1982 and 2007, we interdicted over 225,000 migrants mostly from Cuba, the Dominican Republic, and Haiti.

Throughout our history, the Coast Guard has served with the U.S. Navy to defend our nation. This began with the Quasi-War with France in 1798, and continued through the Civil War, the World Wars, Vietnam, the Persian Gulf War, and Operation Iraqi Freedom.

Today, as a critical component of the U.S. National Fleet, we maintain a high state of readiness to operate as a specialized service alongside the Navy and Marine Corps. The close relationship among our services has evolved over two centuries of cooperation. This enduring relationship is captured in the May 2008 agreement between the Secretaries of Defense and Homeland Security.

The agreement formalizes the use of Coast Guard competencies and resources in support of the National Military Strategy and other national-level defense and security strategies. It lists the following Coast Guard national defense capabilities:

  • Maritime interception and interdiction;
  • Military environmental response;
  • Port operations, security, and defense;
  • Theater security cooperation;
  • Coastal sea control;
  • Rotary wing air intercept;
  • Combating terrorism; and
  • Maritime Operational Threat Response support

These support the unified combatant commanders and require the Coast Guard to execute essential military operations in peacetime, crisis, and war.

Our domestic civil law enforcement and port security expertise are uniquely valuable today as combatant commanders work to build foreign nation capacity for security and governance. In recent years, combatant commanders have requested Coast Guard forces to conduct at-sea interception and antipiracy operations, foreign liaison, and other supporting warfare tasks in all key theaters.

The Coast Guard has been responsible for the security of the ports and waterways of the United States during times of war since the enactment of the Espionage Act of 1917. After World War II, the Magnuson Act of 1950 assigned the Coast Guard an ongoing mission to safeguard U.S. ports, harbors, vessels, and waterfront facilities from accidents, sabotage, or other subversive acts.

Following the terrorist attacks of September 11, 2001, these authorities took on grave new importance. This includes denying terrorists the use of the U.S. maritime domain and the U.S. MTS to mount attacks on our territory, population, or critical infrastructure.

Our authorities were further strengthened with the passage of the Maritime Transportation Security Act of 2002. This designated Coast Guard Captains of the Port as the Federal Maritime Security Coordinators. The Coast Guard thus became the lead agency for coordinating all maritime security planning and operations in our ports and waterways. These activities encompass all efforts to prevent or respond to attacks.

Maritime security is a continuing theme running throughout our proud history of service to America. It requires a breadth of experience and skills—seamanship, diplomacy, legal expertise, and combat readiness. We have honed these skills for more than two centuries. No other federal agency offers this combination of law enforcement and military capabilities, together with the legal authorities to carry them out.

Drug Interdiction

  • Reduce the supply of illegal drugs entering the U.S. via maritime routes through interdiction of smugglers and thei illicit cargos at sea
  • Counter drug trafficking organizations through the use of 35 counterdrug bi-lateral agreements with partner nations

Migrant Interdiction

  • Reinforce the Nation's border security by providing a layered defense to deter, detect, and interdict undocumented migrants attempting to enter the United States illegally
  • Preserve safety of life at sea and respect the human rights of migrants while aboard Coast Guard assets

Defense Readiness

  • Conduct joint operations to support U.S. Combatant Commanders including:
    • Maritime interception/ interdiction operations
    • Military environmental response
    • Port operations, security, and defense
    • Theater security cooperation
    • Coastal sea control operations
    • Rotary-Wing Air Intercept (RWAI) operations
    • Combating terrorism operations
    • Maritime Operational Threat Response (MOTR) support
  • Provide capabilities and resources in support of naval warfare mission areas
  • Function as an armed force at all times as one of the five Services of the Joint Force.

Ports, Waterways, and Coastal Security

  • Develop maritime security regimes
  • Detect, deter, and disrupt maritime terrorist attacks, sabotage, or subversive acts
  • Respond to and recover from attacks that may occur
  • Work with port partners and review vessel and facility security plans to ensure responsible security planning in the private sector
Last Modified 9/5/2014