In order to understand the reaction of the United States to Saddam Hussein's invasion of Kuwait, one must first understand the larger geopolitical framework in which that short war took place. The delicate balance of power that had existed during the Cold War between the United States and its allies on one side, and the Soviet Union and its allies on the other, had by 1990 begun to crumble, as Soviet president Mikhail Gorbachev pushed for further reforms in the Soviet Union, which led to its unraveling.
Saddam Hussein's invasion of the oil rich but tiny country of Kuwait became the first international crisis in a post-Cold War era, when the Soviet Union no longer had the resources or wherewithal to exert its power in the Middle East. Although the United States had backed Iraq in its decade long proxy war against Iran, Iraq had long been an ally of the Soviet Union, and the Soviet Union had long acted as a restraining force on Saddam and his territorial ambitions. Due to the fact that both the Soviet Union and the United States had supported Iraq against Iran during the 1980s, Saddam judged incorrectly that neither of the two superpowers would be in any hurry to intervene if he invaded Kuwait.
One of the main reasons that Saddam and his Iraqi army invaded Kuwait was that the Iran-Iraq war had been incredibly costly, and Iraq owed a great deal of money to both Saudi Arabia and Kuwait, which had leant Iraq money for that war. Those countries had done this because their populations are both majority Sunni Muslim, while Iran has a majority Shiite population. Sunni and Shia have hated each other and fought for dominance since shortly after the death of the prophet Mohammed; both major Islamic sects claim to be the legitimate heirs to the prophet, and each views the other as heretical. Although Iraq, like Iran, was and remains majority Shia, Saddam and his ruling Baath Party was Sunni, and thus Saudi Arabia and Kuwait saw Saddam as a crucial counterweight against Iran.
Yet when Kuwait and Saudi Arabia refused to forgive Iraq's debt after the Iran-Iraq war, Saddam saw an opening. Saudi Arabia does not like to get directly involved in regional conflicts, because of the risk to its oil-dependent economy. Also, even with the Soviet Union weakened, Saddam Hussein did not think that the United States would dare to launch an invasion of a major Soviet ally, at the risk of pulling the Soviets into a direct conflict. What Hussein failed to understand was that President George H. W. Bush had an and long-running friendship with the Saudis, who pleaded for US intervention to help get Saddam out of neighboring Kuwait. Saddam Hussein also failed to understand that the power dynamic between the United States and the Soviet Union had shifted, and that Gorbachev really meant it when he said that the Soviet Union would no longer get involved in outside territorial disputes. Gorbachev had focused...
his presidency on modernizing Soviet domestic policy, instituting economic and political reforms (Glasnost and Perestroika) and this made him unwilling to wade into another possibly disastrous intervention like the Soviet-Afghan War, which had nearly bankrupted the Soviet Union and ended in ignominious defeat.
Moreover, the United States, led by Bush Senior, was eager to demonstrate to the world that it was the only world superpower left, and that its military was far superior to any other in the world. The Iraqi army was considered quite formidable, but Bush Senior knew that it was no match for American airpower, and the decision to repel Saddam’s forces was as much about supporting Saudi Arabia and protecting Kuwait as it was about making a show of power in order to solidify the United States’ position as the only remaining global juggernaut, and a country that nobody should ever mess with.
Bush and his advisors understood that a quick and divisive victory, built on “shock and awe,” would provide a powerful deterrent to any would-be future enemies who might consider testing the United States or its allies.