On 2 August 1990, the forces of Iraq invaded Kuwait. From the first days of the world's response to the Iraq's invasion, Army National Guard soldiers reacted, initially as volunteers, and later as members of mobilized units. During this period, the Guard went through its largest mobilization since the Korean War. The response of Guard soldiers and their families vindicated the trust that the nation had placed in them. Many supports-transportation, quartermaster, command and control headquarters, military police, medical and others answered the call and served in the desert, providing less-heralded but very necessary functions. More than 62,000 Army National Guard soldiers were mobilized, and of these, nearly 39,000 deployed to Southwest Asia. Tensions erupted into a fighting war on 17 January 1991, when Allied air forces initiated a devastating air campaign. The scope of the conflict widened in February when, after a series of skirmishes and battles along the borders of Saudi Arabia, Kuwait and Iraq, the Allied ground offensive began. Six Army National Guard field artillery battalions supported the advance into Iraq. One of these battalions, the 1st Battalion, 158th Field Artillery, Oklahoma Army National Guard, was armed with the Multiple-Launch Rocket System. Field artillerymen of this battalion supported the ground attack by firing salvos of Multiple-Launch Rocket System rockets into Iraq, and continued to support the massive ground offensive with responsive, accurate and devastating fire throughout the campaign. The Multiple-Launch Rocket System rockets were so deadly that the Iraqi soldiers called them "steel rain." The dedicated and selfless service of the Army National Guard in Operation Desert Storm carries on the 355-year National Guard mission of defense of the nation.