Why only the Arizona Memorial?

Probably because of it's dramatic sinking.

The huge explosion was photographed, and i'm sure everyone is familiar with that photo. And if i'm not mistaken, the Arizona was also one of our biggest battleships at the time. Not to mention the huge loss of life on one ship

Blame the Brits - the Japanese got the idea for the torpedo attack from the Taranto raid

Returning to the US in early 1919, Mitchell was appointed the deputy chief of the Air Service, retaining his onestar rank. His relations with superiors continued to sour as he began to attack both the War and Navy Departments for being insufficiently farsighted regarding airpower. His fight with the Navy climaxed with the dramatic bombing tests of 1921 and 1923 that sank several battleships, proving-at least to Mitchell-that surface fleets were obsolete.

Within the Army he also experienced difficulties, notably with his superiors Charles Menoher and later Mason Patrick, and in early 1925 he reverted to his permanent rank of colonel and was transferred to Texas. Although such demotions were not an unusual occurrence at the time-Patrick himself had gone from major general to colonel upon returning to the Corps of Engineers in 1919-the move was nonetheless widely seen as punishment and exile. Not content to remain quiet, when the Navy dirigible "Shenandoah" crashed in a storm and killed 14 of the crew, Mitchell issued his famous statement accusing senior leaders in the Army and Navy of incompetence and "almost treasonable administration of the national defense." He was courtmartialed, found guilty of insubordination, and suspended from active duty for five years without pay. Mitchell elected to resign instead as of 1 February 1926 and spent the next decade continuing to write and preach the gospel of airpower to all who would listen.

The election of Franklin D. Roosevelt, a Navy man, was viewed by Mitchell as advantageous for airpower. In fact, he believed the new president would appoint him as assistant secretary of war for air or perhaps even secretary of defense in a new and unified military organization. Such hopes never materialized. Mitchell died of a variety of ailments including a bad heart and influenza in 1936.

Yamamoto publicly ridiculed US Army General Billy Mitchell's 1920s contention that Japan would, one day, attack the US by surprise on a Sunday morning at a little-known port called Pearl Harbor in far-away Hawaii. "I do not regard relations between the US and Japan from the same angle as General Mitchell. I have never thought of America as a potential enemy, and the naval plans of Japan have never included the possibility of a Japanese-American war."

It was therefore with great frustration and consternation that he watched war clouds gather in the Pacific during the 1930s.