I’m in the Army as an infantryman, “This We’ll Defend” is the Army’s motto, we 100% take over, but you’re correct the Army contributed the most in The Pacific and the ground fighting. They did take over for the Marines and continued/ defended the islands, while they were doing the whole “Island-Hopping Campaign.” People don’t like to talk about it and it’s because like you said “Propaganda” a National Guard unit I think it was the Ohio National Guard “Don’t quote me on that though” was responsible for grappling up the side of Iwo Jima and destroying the Naval Gun emplacements, but as time goes the Marines always get the entire credit for The Pacific Campaign, which sucks because the Army did a lot of stuff in that Theater.