Who uses a racial slur towards Katsumi?
Fighter ace Major Lloyd "Ace" Gruver, of the United States Air Force,  the son of a U.S. Army general, is stationed at Itami Air Force Base near Kobe, Japan. He has been reassigned from combat duties in Korea by General Webster, the father of his fiancée, Eileen.
Airman Joe Kelly, who is Ace's enlisted crew chief, is about to wed a Japanese woman, Katsumi, in spite of the disapproval of the United States military establishment, which will not recognize the inter-racial marriage. The Air Force, including Ace, is against the marriage. Ace and Joe have an argument during which Ace uses a racial slur to describe Katsumi. Ace eventually apologizes, then agrees to be Joe's best man at the wedding.
Ace falls in love with a Japanese entertainer, Hana-ogi, who is a performer for a Takarazuka-like theater company, whom he meets through Katsumi. Eileen realizes that Ace's attentions are no longer focused on her and begins a friendship with a famous Kabuki performer, Nakamura. When she overhears that Joe's house has been under surveillance by the Army, she believes that Ace is in danger and goes there to warn him, where she realizes he is seeing a local woman.
Joe suffers further prejudice at the hands of a particularly nasty colonel, pulling extra duty and all the less attractive assignments. When he and many others who are married to Japanese are targeted for transfer back to the States, Joe realizes that he will not be able to take Katsumi, who is now pregnant. Ace goes to General Webster and pleads Joe's case, asking that he be allowed to remain in Japan. When the General refuses on the grounds that he cannot allow an exception, Ace tells him that he will be in the same situation, since he intends to marry Hana-Ogi. Eileen and her mother are present for the exchange and when Ace apologizes for hurting her, she realizes Ace never loved her the way he loves Hana-Ogi and she leaves to see Nakamura.
Lloyd "Ace" Gruver