National Security

The most powerful military in the world guards the United States of America and protects its allies. This National Security apparatus has had two major overhauls since World War Two as the nation adapted to evolving threats. In this summary, we examine the crucial components of the national strategy and key figures such as the National Security Advisor and National Security Council. We have you covered with the basics of the National Security Act and the more recent Patriot Act. The dramatic shifts in both national and international preparedness have had a major impact on the lives of average citizens.

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Table of contents

    Definition of National Security

    National Security refers to the development of equipment, strategies, and the deployment of personnel to guard the physical safety of a nation.

    The methods of ensuring the National Security of the United States include:

    • Developing a strong military and means to project its influence abroad.

    • Using diplomatic means to develop allies and neutralize threats.

    • Implementing economic strategies to support defense.

    • Devising counterintelligence actions and agencies.

    • Strengthening homeland safety and preparedness.

    • Neutralizing espionage and foreign actions.

    • Designing effective domestic infrastructure.

    National Security and the Constitution

    In the preamble of the Constitution, National Security is ingrained in the opening sentence as common defence.

    We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence…”

    Congress was tasked with declaring war, funding the military, and devising rules for the use and operation of the military. Meanwhile, the President was given the following National Security authority:

    The President shall be Commander in Chief of the Army and Navy of the United States, and of the Militia of the several States, when called into the actual Service of the United States..”

    National Security Strategy

    The concept of National Security is based on the belief that a nation-state has an obligation to plan for threats to its safety from outside forces and other states. This national defense strategy is based upon the power of military forces bolstered by intelligence gathering and sharing. Aside from the traditional definition of military security, other national safety concerns include:

    • Political security (elections, government institutions)
    • Economic security (markets, trade and businesses)
    • Energy security (natural resources and energy products)
    • Homeland defense (transportation and border)
    • Cybersecurity (computer and data infrastructure)
    • Human security (hunger, disease, oppression)
    • Environmental security (natural disasters and climate issues)

    National Security Act

    After World War Two a major overhaul of the nation’s intelligence gathering, operation and military command, and planning apparatus was orchestrated by Congress. Signed into law by President Harry Truman in 1947, the National Security Act organized the massive U.S. military and intelligence structure to better align with Cold War threats and new communication technologies.

    An Act To promote the national security by providing for a Secretary of Defense; for a National Military Establishment; for a Department of the Army, a Department of the Navy, and a Department of the Air Force; and for the coordination of the activities of the National Military Establishment with other departments and agencies of the Government concerned with the national security.” -U.S. Congress.

    The National Security Act and the Military

    The military branches were separated with the removal of the Secretary of War as a position and the branch heads reporting to a Secretary of Defense, subordinate to the President as Commander-in-Chief. The U.S. Air Force was created out of the Army Air Corps, creating a new branch of the military.

    Joint Chiefs of Staff

    The creation of the JCS, or Joint Chiefs of Staff, organized the head of each military branch (Army, Navy, Air Force (newly created), Coast Guard, and Marine Corps.) The Joint Chiefs were tasked with advising the President on military matters, war planning, and defense strategies.

    In 1949, the National Security Act was amended creating the National Military Establishment. In this arrangement, the Department of Defense was organized under a cabinet-level Secretary of Defense.

    Military Branches

    The massive government department known as the Department of Defense organizes and oversees the entire military forces of the U.S.

    • U.S. Army - carries out land operations

    • U.S. Marine Corps - carries out for sea/land operations

    • U.S. Navy- carries out sea operations

    • U.S. Air Force- carries our air operations

    • U.S. Coast Guard- carries our coastal protections (drugs, safety, immigration, and national defense)

    • U.S. Space Force- carries out space operations with a focus on satellite and missile tracking

    The National Security Act and Intelligence Agencies

    The biggest shift brought about by the passage of the National Security Act was the intelligence sharing process. The creation of the Central Intelligence Agency streamlined the process of gathering and sharing information about foreign intelligence and security threats. The line of communication to the Office of the President became more direct as a result.

    The CIA was formed in 1947 as the nation’s intelligence service. The agency gathers intelligence on foreign threats to domestic interests and shares that information with federal policymakers. Undercover operatives in foreign countries, analysts to interpret data, and policy advisors to the Executive Branch help provide high-tech national security.

    Trivia Points: Did you know the 41st President of the United States served as Director of the C.I.A.? George H.W. Bush was Director of Central Intelligence under President Ford from 1976 to 1977. Bush won the 1988 election and served one term as President. His foreign policy experience was significant and events such as the Persian Gulf War and the end of the Cold War occurred during his time in office.

    National Security Agency

    The National Security Agency (N.S.A.) was created in 1952 to collect foreign electronic data that relates to U.S. security interests. In addition, the N.S.A. guards classified U.S. national security data.

    National Seurity, National Security Agency, Baseball cap featuring the Seal of the National Security Agency, StudySmarterFig. 1 Baseball cap featuring the Seal of the National Security Agency

    National Security Council

    The National Security Council was created under the National Security Act of 1947 and amended in 1949 to serve in the President’s Executive Office. According to the Office of the President, the National Security Council is:

    “the President’s principal forum for national security and foreign policy decision making with his or her senior national security advisors and cabinet officials, and the President’s principal arm for coordinating these policies across federal agencies.”

    Source: The White House

    Members of the National Security Council

    The National Security Council is chaired by the President of the United States and includes:

    • The Vice President
    • Secretary of Defense
    • Secretary of Homeland Security
    • Secretary of State
    • Secretary of Energy
    • Secretary of the Treasury
    • Attorney General
    • U.N. Representative
    • other executive agencies, Cabinets, and staff members often attend

    The military advisor is the Chairman of the Joint Chiefs of Staff and the Director of National Intelligence is the intelligence advisor. The President’s primary civilian advisor on national security issues is called the National Security Advisor.

    National Security Advisor

    The National Security Advisor is responsible for serving as the principal advisor to the President on both domestic and international national security matters. The position is by presidential appointment and only requires approval by the U.S. Senate if the candidate is a three- or four-star general/admiral.

    As a senior advisor to the President, he or she (Dr. Condoleeza Rice was the first female) is responsible for presenting classified intelligence and policy suggestions. The National Security Advisor is tasked with providing current, detailed analysis and policy advice on foreign threats and national security interests.

    During national emergencies, the National Security Advisor typically attends meetings in the White House Situation Room or the mobile equivalent. Famous National Security Advisors have included Dr. Condoleeza Rice, Dr. Henry Kissinger, and Dr. Susan Rice. The position has had the potential to be extremely influential as the holder has almost daily, direct access to the President.

    National Security, National Security Advisor, New York on 9/11, StudySmarter Fig 2. New York on 9/11

    The Patriot and Homeland Security Acts

    The 9/11 terror acts resulted in immediate changes to America's National Security structure and operations.

    The Patriot Act

    The Patriot Act (2001) was passed by Congress weeks after the 9/11 terror attacks and signed into law by President George W. Bush. The Congressional vote was clearly bipartisan with a Senate result of 98-1, and 357-66 in the House. The law facilitated increased surveillance and gathering authority of government law enforcement agencies. The purpose was to prevent terrorism, deter future acts of terror, and punish those connected to the execution or funding of terror acts.

    USA Patriot Act stands for: Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism)

    The Patriot Act was followed by the Homeland Security Act (2002) which was similarly supported by most of Congress.

    The Homeland Security Act

    The Department of Homeland Security was created by combining the following agencies:

    • Transportation Security Administration
    • U.S. Secret Service
    • U.S. Coast Guard
    • U.S. Immigration and Customs Enforcement
    • Federal Emergency Management Agency
    • U.S. Citizenship and Immigration Services
    • U.S. Customs and Border Protection
    • Cybersecurity and Infrastructure Security Agency

    National Security - Key takeaways

      • The Constitution organizes the government's role in preparing for the common defence. The President is in charge of the armed forces and military support apparatus while Congress has the power to fund the military and make war.
      • The National Security Act of 1947 organized the massive U.S. military and intelligence structure to better align with Cold War threats and new technologies.
      • The Patriot and Homeland Security Acts broadened government powers as terrorism became a major consideration of national security.
      • The National Security Advisor, National Security Council, and Joint Chiefs of Staff have a vital role in advising the Commander-in-Chief.
      • Major changes to National Security organizations have increased the number of military branches and intelligence agencies as technology and threats have changed.


    1. Fig. 1 Baseball cap featuring the Seal of the National Security Agency ( by Lupus in Saxonia ( licensed by CC BY-SA 4.0 (
    2. Fig 2. New York on 9/11 ( by BaseOn ( licensed by CC BY-SA 4.0 (
    Frequently Asked Questions about National Security

    What is the main purpose of national security? 

    The main purpose of national security is to protect American citizens and institutions.

    What are some examples of national security? 

    Examples of national security include border protection, intercepting attacks on U.S. interests and preventing terrorism.

    What is national security in America? 

    National security is the protection of American safety from domestic and international threats.

    What are national security concerns? 

    National security concerns are threats to national peace that include war, terrorism, extremists and cyber attacks.

    What is national security? 

    National security is the protection of American safety from domestic and international threats. The Department of Homeland Security, National Security Advisor and Security Council all assist in this goal.  The military and executive agencies assist the President in accomplishing this task.

    Test your knowledge with multiple choice flashcards

    This law created increased surveillance operations by law enforcement. 

    This law reorganized the federal government agencies after 9/11.

    According to the U.S. Constitution, the President has the power to fund the military.


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