The following was part of a biography written by Pat Roy detailing Major O'Malley's military involvement....
"Major O’Malley landed on Utah Beach in Normandy on June 6, 1944 on D-day, under heavy enemy fire and was promoted to Major shortly thereafter. Six days later, he assumed command of the 2nd Battalion on June 12, 1944. He led the battalion to its greatest battlefield successes in the liberation of Montebourg and the capture of the key port of Cherbourg on June 26, 1944. These successes were the major objectives of the allies. For his fearless leadership and deep concern for his men, Major O’Malley was considered the best combat leader in the Army by his mentor, Assistant Division Commander Brigadier General Teddy Roosevelt, Jr., son of former U.S. President, Teddy Roosevelt and nephew of former U.S. President, Franklin Delano Roosevelt. BG Teddy Roosevelt, Jr. received the Medal of Honor for his inspiring leadership in the successful landings at Utah Beach.
Repositioned to the Carentan area, Major O’Malley’s Battalion was engaged in fierce fighting against elite enemy forces entrenched in the hedgerows of the Normandy countryside. Although wounded twice, Major O’Malley continued to lead his beloved battalion from his frontline position in the lead company in the attack. Again, his aggressive and fearless leadership endeared him to his men who called him “The Iron Major.”"