Niigata City Peace Monument (Mitokyō Park)

Niigata was designated as one of the four primary targets for the atomic bomb in the July 25, 1945 directive issued by General Thomas Handy to General Carl Spaatz, commanding the United States Army Strategic Air Forces. The directive authorized the 509th Composite Group to deliver "its first special bomb" on one of four cities: Hiroshima, Kokura, Niigata, or Nagasaki, as soon as weather permitted visual bombing after about August 3, 1945.

The Target Committee of the Manhattan Project first selected Niigata at its May 10–11, 1945 meetings at Los Alamos, noting that "Niigata is an important port on the northwest coast of Honshu. Its importance has increased since other ports have been destroyed. It has aluminium, steel, and oil refinery industries, machine tool factories, and serves as a potential center for the dispersal of industry from other urban areas." At the time, the target list read: Kyoto, Hiroshima, Yokohama, Kokura Arsenal, and Niigata.

However, Niigata occupied the lowest priority position throughout the selection process. By late July 1945, two factors worked against it. First, the city's industrial zones — primarily the Nippon Oil Company refinery (日本石油) and the Showa Oil Company (昭和石油) facilities — were geographically separated from the densely populated residential areas, making Niigata a poor candidate for demonstrating the bomb's full destructive potential on a concentrated urban target. The Target Committee minutes noted that "the industrial area and the residential areas containing small factories are far enough apart that this type of attack is not suitable." Second, Niigata lay much farther from Tinian than the other three target cities (all clustered in western Honshu and northern Kyushu), which meant significantly greater fuel consumption for a B-29 carrying a five-ton bomb, and the city was regarded as too small a target.

In the orders for the first mission, issued in early August 1945, Niigata no longer appeared: Hiroshima was named as the primary target with Kokura and Nagasaki as alternates, and Niigata was not selected even as an alternate on August 6 or August 9.

Niigata had experienced limited conventional air raids during the war. The most notable attack occurred on August 10, 1945, when U.S. Navy carrier aircraft struck the port area, damaging oil storage facilities and harbor infrastructure. After the atomic bombings of Hiroshima and Nagasaki, the prefectural governor issued a notice on August 11 urging residents to evacuate, and much of the population left the city centre.

The Niigata City Peace Monument (新潟市平和祈念碑) was erected on August 10, 1998 (Heisei 10) in Mitokyō Park (水戸教公園) at Hibari-machi, Chuo Ward, as a postwar 50th anniversary project. The park overlooks Niigata Port from an elevated position historically used by mitokyō (水戸教) — Edo-period harbor pilots who guided ships safely into port. The monument commemorates not only Japanese war dead but also foreign nationals who died as prisoners of war or forced laborers on Japanese soil. An annual flower-offering ceremony (献花式) is held on August 10, the anniversary of the Niigata air raids, attended by city officials and citizens.

Niigata's status as a "city that escaped the atomic bomb" (原爆を免れた街) has become an important element of local peace education. Unlike Kokura, which developed the concept of "the Luck of Kokura" (小倉の運), Niigata's near-miss with nuclear destruction remains relatively little known both domestically and internationally — a phenomenon that historian Alex Wellerstein has termed "neglected Niigata."