Question: Who was president of the nation where Eckelson Township is located when the city containing Aioi Bridge was bombed?

full_context: Document 1: Atomic bombings of Hiroshima and Nagasaki: By August 1945, the Allies' Manhattan Project had produced two types of atomic bombs, and the 509th Composite Group of the United States Army Air Forces (USAAF) was equipped with the specialized Silverplate version of the Boeing B - 29 Superfortress that could deliver them from Tinian in the Mariana Islands. Orders for atomic bombs to be used on four Japanese cities were issued on July 25. On August 6, the U.S. dropped a uranium gun - type (Little Boy) bomb on Hiroshima, and American President Harry S. Truman called for Japan's surrender, warning it to ``expect a rain of ruin from the air, the like of which has never been seen on this earth. ''Three days later, on August 9, a plutonium implosion - type (Fat Man) bomb was dropped on Nagasaki. Within the first two to four months following the bombings, the acute effects of the atomic bombings had killed 90,000 -- 146,000 people in Hiroshima and 39,000 -- 80,000 in Nagasaki; roughly half of the deaths in each city occurred on the first day. During the following months, large numbers died from the effect of burns, radiation sickness, and other injuries, compounded by illness and malnutrition. In both cities, most of the dead were civilians, although Hiroshima had a sizable military garrison.
Document 2: Little Boy: ``Little Boy ''was the codename for the atomic bomb dropped on the Japanese city of Hiroshima on 6 August 1945 during World War II by the Boeing B - 29 Superfortress Enola Gay, piloted by Colonel Paul W. Tibbets, Jr., commander of the 509th Composite Group of the United States Army Air Forces. It was the first atomic bomb to be used in warfare. The Hiroshima bombing was the second artificial nuclear explosion in history, after the Trinity test, and the first uranium - based detonation. It exploded with an energy of approximately 15 kilotons of TNT (63 TJ). The bomb caused significant destruction to the city of Hiroshima and its occupants.
Document 3: Eckelson Township, Barnes County, North Dakota: Eckelson Township is a civil township in Barnes County, North Dakota, USA. As of the 2000 census, its population was 95.
Document 4: Atomic bombings of Hiroshima and Nagasaki: By August 1945, the Allies' Manhattan Project had produced two types of atomic bomb, and the 509th Composite Group of the United States Army Air Forces (USAAF) was equipped with the specialized Silverplate version of the Boeing B - 29 Superfortress that could deliver them from Tinian in the Mariana Islands. Orders for atomic bombs to be used on four Japanese cities were issued on July 25. On August 6, one of its B - 29s dropped a Little Boy uranium gun - type bomb on Hiroshima. Three days later, on August 9, a Fat Man plutonium implosion - type bomb was dropped by another B - 29 on Nagasaki. The bombs immediately devastated their targets. Over the next two to four months, the acute effects of the atomic bombings killed 90,000 -- 146,000 people in Hiroshima and 39,000 -- 80,000 people in Nagasaki; roughly half of the deaths in each city occurred on the first day. Large numbers of people continued to die from the effects of burns, radiation sickness, and other injuries, compounded by illness and malnutrition, for many months afterward. In both cities, most of the dead were civilians, although Hiroshima had a sizable military garrison.
Document 5: Homestead Grays Bridge: The Homestead Grays Bridge, also known as the (Homestead) High Level Bridge, was built in 1936 and spans the Monongahela River between Homestead Borough and the southernmost tip of Pittsburgh's Squirrel Hill neighborhood. It is notable as the first bridge to incorporate the Wichert Truss, which uses a quadrilateral shape over each support, into its design. This made the truss statically determinate, so that forces in the structural members could be calculated.
Document 6: Atomic bombings of Hiroshima and Nagasaki: The staff officer went to the airport and took off for the southwest. After flying for about three hours, while still nearly 160 km (100 mi) from Hiroshima, he and his pilot saw a great cloud of smoke from the bomb. After circling the city in order to survey the damage they landed south of the city, where the staff officer, after reporting to Tokyo, began to organize relief measures. Tokyo's first indication that the city had been destroyed by a new type of bomb came from President Truman's announcement of the strike, sixteen hours later.
Document 7: Uxbridge Township, Barnes County, North Dakota: Uxbridge Township is a civil township in Barnes County, North Dakota, United States. As of the 2000 census, its population was 111.
Document 8: Atomic bombings of Hiroshima and Nagasaki: Due to crosswind, the bomb missed the aiming point, the Aioi Bridge, by approximately 800 ft (240 m) and detonated directly over Shima Surgical Clinic. It released the equivalent energy of 16 kilotons of TNT (67 TJ), ± 2 kt. The weapon was considered very inefficient, with only 1.7% of its material fissioning. The radius of total destruction was about 1 mile (1.6 km), with resulting fires across 4.4 square miles (11 km).
Document 9: Valley Township, Barnes County, North Dakota: Valley Township is a civil township in Barnes County, North Dakota, USA. As of the 2000 census, its population was 565.
Document 10: Atomic bombings of Hiroshima and Nagasaki: Hiroshima was the primary target of the first atomic bombing mission on August 6, with Kokura and Nagasaki as alternative targets. The 393d Bombardment Squadron B-29 Enola Gay, named after Tibbets' mother and piloted by Tibbets, took off from North Field, Tinian, about six hours' flight time from Japan. Enola Gay was accompanied by two other B-29s: The Great Artiste, commanded by Major Charles Sweeney, which carried instrumentation, and a then-nameless aircraft later called Necessary Evil, commanded by Captain George Marquardt, which served as the photography aircraft.
Document 11: Tuti Bridge: The Tuti-Khartoum Bridge is the first among a series of bridges that will connect the cities of Khartoum, Omdurman and Bahri (North Khartoum), and will help to alleviate traffic throughout the cities. The development has immediately commercialised the previously isolated Tuti Island.
Document 12: Eckelson, North Dakota: Eckelson is an unincorporated community in Barnes County, North Dakota, United States. Eckelson is west of Sanborn and north of Interstate 94, which has an exit serving Eckelson.
Document 13: Meadow Lake Township, Barnes County, North Dakota: Meadow Lake Township is a civil township in Barnes County, North Dakota, USA. As of the 2000 census, its population was 93. The township is located in Public Land Survey System Township 138N, Range 61W.
Document 14: Aioi Bridge: The is an unusual "T"-shaped three-way bridge in Hiroshima, Japan. The original bridge, constructed in 1932, was the aiming point for the 1945 Hiroshima atom bomb because its shape was easily recognized from the air. Although the bridge was not destroyed by the atomic blast, it did sustain heavy damage. After the war, the bridge was repaired and remained in service for nearly four decades, before it was replaced by a new bridge (built as a replica) in 1983. A surviving portion of a floor girder from the original bridge was subsequently donated to the Hiroshima Peace Memorial Museum.
Document 15: Nhật Tân Bridge: The Nhật Tân Bridge (or "Vietnam–Japan Friendship Bridge") is a cable-stayed bridge crossing the Red River in Hanoi, inaugurated on January 4, 2015. It forms part of a new six-lane highway linking Hanoi and Noi Bai International Airport. The project is funded by a Japan International Cooperation Agency ODA loan.
ground_truth: President Truman
sub_queries: Eckelson Township >> country Answer: US
Aioi Bridge >> located in the administrative territorial entity Answer: Hiroshima
who was the US president when #2 was bombed Answer: President Truman