The movie is based on the novel by Leon Uris, who also wrote the screenplay, and was produced and directed by Raoul Walsh. It received an Academy Award nomination for Scoring of a Dramatic or Comedy Picture.
Although the story takes place in 1942, all of the women's clothing and hairstyles, particularly those of Nancy Olson, Dorothy Malone and Mona Freeman, are strictly 1954; the sole exception is Anne Francis, whose appearance does actually imply the correct era at least to some extent.
The attack transport USS Pickaway (APA-222) shown at dock side after Pat and Andy's wedding; and just before the battle of Tarawa; wasn't commissioned until Dec 12 1944. This ship wasn't yet built for Tarawa.
When the unit first comes under enemy air attack, the path of explosions on the ground take a sharp turn from the left to follow the men along the road. It is physically impossible for any plane to turn sharply enough to leave that sharp a pattern on the ground