In 1990, fellow Arab Gulf states refused to endorse Iraqi leader Saddam Hussein's plan to cut production and raise the price of oil, leaving him frustrated and paranoid. Iraq had incurred a mountain of debt during its war with Iran that had lasted for most of the previous decade, and the Iraqi President felt that his Arab brothers were conspiring against him by refusing to raise oil prices. Therefore, after weeks of massing troops along the Iraq-Kuwait border and accusing Kuwait of various crimes, Hussein sent seven divisions of the Iraqi Army into Kuwait in the early morning hours of 2 August 1990. The invasion force of 120,000 troops and 2,000 tanks quickly overwhelmed Iraq's neighbor to the south, allowing Hussein to declare, in less than a week, that Kuwait was his nation's nineteenth province. The United Nations responded quickly, passing a series of resolutions that condemned the invasion, called for an immediate withdrawal of Iraqi troops from Kuwait, imposed a financial and trade embargo on Iraq, and declared the annexation void.
Regarding Iraq's actions as a threat to a vital interest of the US, namely the oil production capability of the Persian Gulf region, President George Bush ordered warplanes and ground forces to Saudi Arabia after obtaining King Fahd's approval. Iraqi troops had begun to mass along the Saudi border, breaching it at some points, and indicating the possibility that Hussein's forces would continue south into Saudi Arabia's oil fields. Operation DESERT SHIELD, the US military deployment to first defend Saudi Arabia grew rapidly to become the largest American deployment since the Southeast Asia Conflict. The Gulf region was within US Central Command's (CENTCOM) area of responsibility. Eventually, 30 nations joined the military coalition arrayed against Iraq, with a further 18 countries supplying economic, humanitarian, or other type of assistance.
Carriers in the Gulf of Oman and the Red Sea responded, US Air Force interceptors deployed from bases in the United States, and airlift transports carried US Army airborne troopers to Saudi Arabia. Navy prepositioning ships rushed equipment and supplies for an entire marine brigade from Diego Garcia in the Indian Ocean to the gulf. During the next six months the United States and its allies built up a powerful force in the Arabian peninsula. The navy also began maritime intercept operations in support of a US-led blockade and United Nations sanctions against Iraq.
Coalition forces, specifically XVIII Airborne Corps and VII Corps, used deception cells to create the impression that they were going to attack near the Kuwaiti boot heel, as opposed to the "left hook" strategy actually implemented. XVIII Airborne Corps set up "Forward Operating Base Weasel" near the boot heel, consisting of a phony network of camps manned by several dozen soldiers. Using portable radio equipment, cued by computers, phony radio messages were passed between fictitious headquarters. In addition, smoke generators and loudspeakers playing tape-recorded tank and truck noises were used, as were inflatable Humvees and helicopters.
On 17 January 1991, when it became clear that Saddam would not withdraw, Desert Shield became Desert Storm.