defense mechanism, in psychoanalysis, any of a variety of unconscious personality reactions which the ego uses to protect the conscious mind from threatening feelings and perceptions. Sigmund Freud first used defense as a psychoanalytic term (1894), but he did not break the notion into categories, viewing it as a singular phenomenon of repression. His daughter, Anna Freud, expanded on his theories in the 1930s, distinguishing some of the major defense mechanisms recognized today. Primary defense mechanisms include repression and denial, which serve to prevent unacceptable ideas or impulses from entering the conscience. Secondary defense mechanisms—generally appearing as an outgrowth of the primary defense mechanisms—include projection, reaction formation, displacement, sublimation, and isolation.

civil defense, nonmilitary activities designed to protect civilians and their property from enemy actions in time of war. A civil defense program usually includes measures taken during peace (e.g., building home shelters or air raid warning practice), measures to warn civilians of an impending attack, to protect them during attack, and to save their lives and property after attack. Civil defense grew in proportion to the use of aircraft in modern warfare, becoming significant during World War II, when both sides engaged in the strategic bombing of civilian populations. After World War II the existence of nuclear weapons, the development of long-range bombers and missiles, and the ever-present possibility of war encouraged the establishment of comprehensive civil defense systems. The principal U.S. civil defense agency was established by executive order in 1950, and in 1961 civil defense functions were transferred to the Defense Dept. Opinion in the United States has traditionally been divided over the value of civil defense programs. Opponents of civil defense have maintained that, given the destructiveness of modern weapons, warning and shelter systems are useless and merely encourage war hysteria. Proponents of civil defense have asserted that, since a major danger from a nuclear attack is radioactive fallout, an adequate shelter program can save the lives of a large portion of the population. After the beginnings of a détente with the Soviet Union and the People's Republic of China in the 1970s, interest in civil defense in the United States, which peaked at the height of the cold war, began to decline; that decline was furthered by the break up of the Soviet empire. However, most industrialized countries still maintain some form of civil defense.

Strategic Defense Initiative (SDI), U.S. government program responsible for research and development of a space-based system to defend the nation from attack by strategic ballistic missiles (see guided missile). The program is now administered by the Missile Defense Agency (originally the Strategic Defense Initiative Office), a separate agency in the U.S. Dept. of Defense. SDI, popularly referred to as "Star Wars," was announced by President Ronald Reagan in a speech in Mar., 1983, and was derided by his critics as unrealistic. Space programs from other agencies and services were brought together in the organization. It has investigated many new technologies, including ground-based lasers, space-based lasers, and automated space vehicles. Critics argued that the original SDI program would encourage the militarization of space and destabilize the nuclear balance of power, and was technologically infeasible, based on untested technologies, and unable to defend against cruise missiles, airplanes, or several other possible delivery systems. In addition, some countermeasures to SDI technologies, such as decoy missiles and shielding of armed missiles, would be simple to implement. In 1987 the Soviet Union revealed it had a similar program.

The end of the cold war led to criticism that SDI was unnecessary, and in 1991 President G. H. W. Bush called for a more limited version using rocket-launched interceptors based on the ground at a single site. In 1993, SDI was reorganized as the Ballistic Missile Defense Organization (BMDO). The more limited system, called the National Missile Defense (NMD), is intended to protect all 50 states from a rogue missile attack, but the deployment of such a system was forbidden under the 1972 Anti-Ballistic Missile (ABM) Treaty. Russia opposed the NMD plan but, under President Putin, also proposed a mobile, pan-European missile defense system with a similar purpose that would not violate the ABM treaty. In 2001, President George W. Bush called for accelerated development of the NMD system, and subsequently withdrew from the ABM treaty to permit the system's development and deployment. Apparently successful early tests of the U.S. system were later revealed to have occurred after the odds of success had been enhanced (1984, 1991). Subsequent tests were generally more successful, although flawed or limited in certain respects, but tests in 2002, 2004, and 2005 involved failures. In 2002, President Bush ordered the deployment of a modest missile defense system by 2004, with interceptors based at sea and at Fort Greely, Alaska, and Vandenberg Air Force Base, Calif., and several interceptor missiles were emplaced by the end of 2004. Also in 2002, the BMDO was renamed the Missile Defense Agency (MDA). In addition to NMD, the MDA is also working to develop missile defenses for the battlefield as part of the Theater Missile Defense program.

National Defense Education Act (NDEA), federal legislation passed in 1958 providing aid to education in the United States at all levels, public and private. NDEA was instituted primarily to stimulate the advancement of education in science, mathematics, and modern foreign languages; but it has also provided aid in other areas, including technical education, area studies, geography, English as a second language, counseling and guidance, school libraries and librarianship, and educational media centers. The act provides institutions of higher education with 90% of capital funds for low-interest loans to students. NDEA also gives federal support for improvement and change in elementary and secondary education. The act contains statutory prohibitions of federal direction, supervision, or control over the curriculum, program of instruction, administration, or personnel of any educational institution.

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.

Defense Advanced Research Projects Agency (DARPA), U.S. government agency administered by the Department of Defense (see Defense, United States Department of). It was established in 1958, in reaction to the successful launch of Sputnik by the USSR, as the Advanced Research Projects Agency. Although DARPA is only one of many military agencies administering research and development funds, it has been crucial to the development of several important technologies, especially military computers and the Internet. It funds a high percentage of all artificial intelligence research in the United States, as well as significant projects in microelectronics, materials, and behavioral science.

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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