IWO: Bloodbath in the Bonins (2015)

Iwo Jima was a critical point on the flight path of US bombers from their Saipan bases to their Japanese targets. The island would be a refuge for malfunctioning or damaged bombers coming or going. An obvious target for a US amphibious assault, the Japanese had reinforced the garrison and dug miles of tunnels the length and breadth of the island. Their goal was to inflict maximum casualties on the Americans to force them to reconsider the seemingly inevitable invasion of Japan. The resulting battle was brutal, even by the standards of the Pacific War.