At a superpowers summit meeting in Washington, D.C., U.S. President George H.W. Bush and Soviet leader Mikhail Gorbachev sign a historic agreement to end production of chemical weapons and begin the destruction of both nations’ sizable reserves of them. According to the agreement, on-site inspectors from both countries would observe the destruction process. The treaty, which called for an 80 percent reduction of their chemical weapon arsenals, was part of an effort to create a climate of change that would discourage smaller nations from stockpiling and using the lethal weapons. First developed during World War I, most countries in the world were in possession of the technology needed to build chemical weapons by 1990, and some, such as Iraq, had engaged in chemical warfare in preceding years. The United States and Russia began destroying their chemical weapons arsenals in the early 1990s. In 1993, the U.S., Russia, and 150 other nations signed a comprehensive treaty banning chemical weapons. The U.S. Senate ratified the treaty in 1997.