On Iwo Jima, McCarthy was the company commander of G Co. 2nd Battalion 24th Marines. He landed on yellow beach 2 alongside the 23rd Marines. On D plus 3, the 24th RCT relieved the 25th.
On Iwo Jima, McCarthy was the leader of G Company within the 2nd Battalion, 24th Marines. He landed on Yellow Beach 2 alongside the 23rd Marines and later relieved the 25th RCT on D plus 3.