What do the battle of the B ulge and the battle of Iwo Jima have in common?

The "Bulge" was the US Army's greatest battle during WW2; "Iwo Jima" was the greatest US Marine Corps battle in it's history. Nothing. One was an amphibious landing and other wasn't. One involved battles with heavy armored tanks and the other didn't. One was in winter and the other was on a sunny Pacific island. Okay, maybe both was a desperate last-stand fight by an enemy that was losing the war.