initiative, the originating of a law or constitutional amendment by popular petition. It is intended to allow the electorate to initiate legislation independently of the legislature. This direct form of legislation, together with the referendum, was known in Greece and other early democracies. It is practiced in Switzerland. In the United States the initiative was recognized as early as 1777 in the first constitution of Georgia. It was subsequently adopted by a number of states and may apply also on local and city government levels. There are two kinds of initiative, direct and indirect. In both kinds of initiative a certain number of signatures (usually from 5% to 15% of the electorate in the district concerned) must appear on the petition that proposes the constitutional amendment or legislation. In direct initiative the proposed law is voted on in the next election, or in a special election, after a petition with the required number of signatures has been filed with state or local officials. In indirect initiative the petition goes directly to the legislature and reaches the people only if the legislature fails to enact it into law. In the 1990s ballot initiatives became increasingly popular as various interest groups sought to win approval of measures they supported.

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.

Central European Initiative, organization founded in 1991 to promote economic and political cooperation in the region between the Adriatic and Baltic seas. Members include Austria, Bosnia and Herzegovina, Croatia, the Czech Republic, Hungary, Italy, Macedonia, Poland, Slovakia, and Slovenia. Albania, Bulgaria, Belarus, Moldova, Romania, and Ukraine are associate members. The organization has initiated projects relating to agriculture and small-business development, transportation links among member countries, minority rights, and youth exchange.

Electoral devices by which voters express their wishes regarding government policy or proposed legislation. Obligatory referenda are those required by law. Optional referenda are put on the ballot when a sufficient number of voters sign a petition demanding that a law passed by the legislature be ratified by the people. Obligatory and optional referenda should be distinguished from the voluntary referenda that legislatures submit to voters to decide an issue or to test public opinion. Initiatives are used to invoke a popular vote on a proposed law or constitutional amendment. Direct initiatives are submitted directly to the public after approval by a required number of voters; indirect initiatives are submitted to the legislature. Switzerland has held about half the world's national referenda. Referenda also are common at the local and state level in the U.S. In the late 20th century, referenda were employed more frequently, particularly in Europe, to decide public policy on voting systems, treaties and peace agreements (e.g., the Maastricht Treaty), and social issues. Seealso plebiscite.

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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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