 2nd Battalion , 9th Marines ( 2 / 9 ) was an infantry battalion of the United States Marine Corps . Formed during World War I , the unit played an instrumental role in the defeat of the Japanese forces in the Battles of Guam and Iwo Jima during the World War II . The battalion distinguished itself in the defense of Khe Sanh during the Vietnam War , and later participated in an ill fated invasion of Koh Tang Island in Southeast Asia , with the intention of rescuing the crew of the SS Mayaguez . During Operation Desert Storm , the battalion served as the lead battalion for the III Marine Expeditionary Force ( III MEF ) . 
 2nd Battalion , 9th Marines ( 2 / 9 ) was an infantry battalion of the United States Marine Corps . Formed during World War I , the unit played an instrumental role in the defeat of the Japanese forces in the Battles of Guam and Iwo Jima during the World War II . The battalion distinguished itself in the defense of Khe Sanh during the Vietnam War , and later participated in an ill fated invasion of Koh Tang Island in Southeast Asia , with the intention of rescuing the crew of the SS Mayaguez . During Operation Desert Storm , the battalion served as the lead battalion for the III Marine Expeditionary Force ( III MEF ) . 
2nd Battalion , 9th Marines ( 2 / 9 ) was an infantry battalion of da United States Marine Corps . Formed durin World War I , the unit played an instrumental role in the defeat of tdaJapanese forces in the Battles of Guam and Iwo Jima ddurinthe World War II . Thdaattalion distinguished itself in thedafense of Khe Sanh dudurinhe Vietnam War , and later participated in an ill fated invasion of Koh Tang Island in Southeast Asia , with the daention of rescuing the cda of the SS Mayaguez . During Operation Desert Storm , the battalion served as the ledabattalion for the IIIdarine Expeditionary Force ( III MEF ) .