Defense

Defense, United States Department of, executive department of the federal government charged with coordinating and supervising all agencies and functions of the government relating directly to national security and military affairs. Based in the Pentagon, it is divided into three major subsections—the U.S. Army, the U.S. Navy, and the U.S. Air Force. Among the many Defense Dept. agencies are the Missile Defense Agency (see Strategic Defense Initiative), the Defense Advanced Research Projects Agency, the Defense Intelligence Agency, the National Geospatial-Intelligence Agency, and the National Security Agency. The department also operates several joint service schools, including the National War College.

Creation

The Dept. of Defense was created by the National Security Act of 1947 by combining the Depts. of War and Navy and was called the National Military Establishment; it became the Dept. of Defense when the act was amended (1949). James V. Forrestal pioneered in this reorganization. Under the act, the Secretary of Defense—appointed by the President with the consent of the Senate—supervises the entire military. Under the Secretary of Defense is the Joint Chiefs of Staff made up of its chairperson, a senior military officer, the heads of the three main services, and the Commandant of the Marine Corps. The Secretary of the Army, the Secretary of the Navy, and the Secretary of the Air Force—made cabinet members by the act of 1947—were subordinated (1949) to give the Secretary of Defense full cabinet authority over the department.

History

The new defense establishment received its first test in the Korean War. It was generally agreed that the department revealed a capability to react quickly to crisis, but there was criticism that too much reliance had been placed on strategic air forces and nuclear weapons to the neglect of conventional military forces. The Eisenhower administration, concerned about controlling military expenditures, emphasized deterring a nuclear attack with massive retaliation (see nuclear strategy), despite critics who advocated additional expenditures on conventional forces.

Under Secretary of Defense Robert S. McNamara (1961-68), the department aimed for a more balanced military program and established a new layer of civilian officials who imported civilian management techniques. In general, the administrations of Presidents John F. Kennedy and Lyndon Johnson aimed for a stronger conventional capability but still failed with their counterinsurgency strategy in the Vietnam War.

During the cold war, the Dept. of Defense became a major economic force, mostly through its massive purchases and research investments (see Defense Advanced Research Projects Agency). However, the breakup of the USSR and the resultant reductions in defense spending have negatively affected civilian industries that supplied the Dept. of Defense. By 1997 the department had begun a "defense reform initiative," intended to streamline and modernize what had become one of the world's largest organizations.

In criminal law, an affirmative defense (e.g., to a murder charge) alleging that the defendant used serious force necessarily for self-protection. The claim of self-defense must normally rely on a reasonable belief that the other party intended to inflict great bodily harm or death and that avoidance by retreating was impossible. Seealso homicide.

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In psychoanalytic theory, an often unconscious mental process (such as repression) that makes possible compromise solutions to personal problems or conflicts. The compromise generally involves concealing from oneself internal drives or feelings that threaten to lower self-esteem or provoke anxiety. The term was first used by Sigmund Freud in 1894. The major defense mechanisms are repression, the process by which unacceptable desires or impulses are excluded from consciousness; reaction formation, a mental or emotional response that represents the opposite of what one really feels; projection, the attribution of one's own ideas, feelings, or attitudes (especially blame, guilt, or sense of responsibility) to others; regression, reversion to an earlier mental or behavioral level; denial, the refusal to accept the existence of a painful fact; rationalization, the substitution of rational and creditable motives for the true (but threatening) ones; and sublimation, the diversion of an instinctual desire or impulse from its primitive form to a more socially or culturally acceptable form. Seealso ego; neurosis; psychoanalysis.

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All nonmilitary actions taken to reduce loss of life and property resulting from enemy action. The threat of aerial attack on cities led to organized civil-defense planning in World War II. The British government provided its people with gas masks, and nearly all countries trained citizens in fire fighting, rescue, and first aid. Blackouts reduced the glow from city lights that could guide enemy pilots; sirens warned of bombing attacks, and citizens took cover in air-raid shelters, basements, and subways. The postwar threat of nuclear attack prompted civil authorities to mark buildings that offered the best shelter from fallout. By the 1970s the West had largely abandoned civil-defense preparations as it became clear that surviving a direct nuclear attack was unlikely.

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also called Star Wars

Proposed U.S. strategic defense system against nuclear attacks. Announced as a 20-year, $20 billion effort by Pres. Ronald Reagan in 1983, SDI was intended to defend the U.S. from a full-fledged Soviet attack by intercepting ICBMs in flight. The interception was to be effected by technology not yet developed, including space- and ground-based laser stations and air- and ground-based missiles. The space component of SDI led to its being derisively dubbed “Star Wars” after the popular film. Though the program was roundly criticized by opposition politicians and arms-control advocates as unworkable and as a dangerous violation of the Antiballistic Missile (ABM) Treaty of 1972, Congress granted initial funding for it. Early development efforts were largely unsuccessful, and with the fall of the Soviet Union in 1991 the concept lost urgency. During the Bush and Clinton administrations, ballistic missile defense was scaled back to focus on protecting the U.S. from limited attack by a “rogue” state or a single accidentally launched missile. In 2002 the U.S. withdrew from the ABM treaty to begin active testing of a limited antimissile program. Seealso antiballistic missile.

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Defense or defence (see -ce/-se) may refer to:

The tactics and strategy of defending against attack:

• Defense (military)
• Defense (sport)
• Defender (soccer), a specialist defensive player in association football
• Defenceman (ice hockey), a specialist defensive player in ice hockey
• a Chess opening as created in reply by Black
• Defense (legal)
• Self-defense
• Civil defense

In politics and economics:

• National security
• Defense minister
• International security
• The defense industry
• Defense contractor, a company that provides defense-related services

Concepts in law:

• Self-defense (theory)
• Defense of property

In psychology:

• Defence mechanism

It may also refer to:

• A euphemism for war or the military
• Defense of a doctoral thesis, also called viva voce; see Thesis committee
• La Défense, a business district in Paris
• The Grande Arche, commonly known as Arche de la Défense, a monument in the Parisian district of the same name
• 'DeFence', an interactive conceptual art project for freedom of cohabitation
• The Haganah (in Hebrew: "The Defence"), a paramilitary organization in British Palestine
• Tower defense, a genre of video game
• The pharmaceutical Cimetidine, used for treating gastric ulcers