The Battle of Iwo Jima began 75 years ago today, on Feb. 19, 1945. The capture of the 21 square kilometer island was expected to "only" take a few days, but it ended up requiring five weeks due to the elaborate dug-in defenses (hidden artillery, mortars, land mines, tunnels and bunkers) that Lt. Gen. Tadamichi Kuribayashi had in place, the ability of the Imperial Japanese Army and Navy forces to persevere under unimaginably harsh conditions, and the U.S. Navy's unfortunately short and eventually ineffective pre-invasion bombardment.

Although there was a heated public discussion in the United States after the battle began over the merits of taking Iwo Jima in proportion to the extremely high casualties (eventually, more than 6,800 U.S. personnel were killed, and nearly approximately 19,000 wounded), it is clear now (as it was then) that the joint efforts, led by the U.S. Marine Corps, to take the island was a decisive game-changer.

Specifically, the reasons for taking Iwo Jima were numerous and can be summarized as follows: