The Republican Guard was not Iraq's largest military force, but it was unquestionably the most politically important. Created by Saddam to protect his regime, the Guard received better equipment, better training, and better pay than regular Iraqi forces. Its officer corps was personally loyal to Saddam. Its mission was as much to protect Saddam from his own military and population as to fight external enemies.

The Guard's performance during the Gulf War was mixed. Against coalition forces equipped with superior technology and doctrine, the Guard units took catastrophic losses. The divisions engaged during the left hook were largely destroyed. Republican Guard vehicles burned in the desert. Survivors retreated north.

But the Guard was not annihilated. Estimates suggest that between 30 and 50 percent of Republican Guard personnel and perhaps 30 percent of their equipment survived the 100-hour ground war. This was not insignificant. The Guard had access to additional equipment held in stockpiles around Iraq. Surviving units could be reconstituted.

Militarily, the decision to cease fire after 100 hours meant that the destruction of the Republican Guard was incomplete. Strategically, allowing Saddam to retain control of the Guard was a political calculation. The Bush administration had decided against invading Iraq and overthrowing Saddam. A severely weakened Republican Guard seemed to offer Saddam insufficient capability to threaten the region further, yet sufficient capability to control Iraq internally.

This calculation proved catastrophically wrong.

The Republican Guard, reconstituted and re-equipped in the years following the Gulf War, became the instrument through which Saddam crushed Kurdish and Shiite uprisings. The Guard was used to suppress dissent and maintain regime control. It also became the organization that Saddam relied upon to deter Iranian pressure and maintain Iraq's military capability.

When the 2003 Iraq War began, the Republican Guard was the first unit to be systematically destroyed by American forces. Elements of the Guard, equipped with newer equipment and rebuilt to roughly pre-Gulf War strength, were defeated again in the battles for Baghdad and other key positions.

The decision to halt the 1991 ground war before destroying the Republican Guard completely was thus one of the war's most consequential choices. It freed Saddam to restore control over Iraq's fractious population. It enabled him to suppress Kurdish and Shiite nationalism. It gave him the military force necessary to resist American and international pressure for the next twelve years. When the next war came, the Guard had to be destroyed again, at greater cost and with more lasting consequences.

The Republican Guard's survival in 1991 thus planted the seeds for the catastrophe that followed in 2003.