Question: Who was the president of the country containing Waterfront Park when the city over which Little Boy was detonated was bombed?

<P0-S0> the annual southampton boat show is held in september each year, with over 600 exhibitors present. <P0-S1> it runs for just over a week at mayflower park on the city's waterfront, where it has been held since 1968. the boat show itself is the climax of sea city, which runs from april to september each year to celebrate southampton's links with the sea. <SEP> <P1-S0> 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. <P1-S1> 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. <P1-S2> ''three days later, on august 9, a plutonium implosion - type (fat man) bomb was dropped on nagasaki. <P1-S3> 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. <P1-S4> during the following months, large numbers died from the effect of burns, radiation sickness, and other injuries, compounded by illness and malnutrition. <P1-S5> in both cities, most of the dead were civilians, although hiroshima had a sizable military garrison. <SEP> <P2-S0> The staff officer went to the airport and took off for the southwest. <P2-S1> 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. <P2-S2> 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. <P2-S3> 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. <SEP> <P3-S0> Waterfront Park is a public park on the Central Waterfront, Downtown, Seattle, Washington, USA. <P3-S1> Designed by the Bumgardner Partnership and consultants, it was constructed on the site of the former Schwabacher Wharf (Pier 58). <SEP> <P4-S0> The uranium-based Little Boy device became the first nuclear weapon used in war when it was detonated over the Japanese city of Hiroshima on 6 August 1945. <P4-S1> Two major types of atomic bombs were developed by the United States during World War II: a uranium-based device (codenamed "Little Boy") whose fissile material was highly enriched uranium, and a plutonium-based device (see Trinity test and "Fat Man") whose plutonium was derived from uranium-238. <P4-S2> Exploding with a yield equivalent to 12,500 tonnes of TNT, the blast and thermal wave of the bomb destroyed nearly 50,000 buildings and killed approximately 75,000 people (see Atomic bombings of Hiroshima and Nagasaki). <P4-S3> Initially it was believed that uranium was relatively rare, and that nuclear proliferation could be avoided by simply buying up all known uranium stocks, but within a decade large deposits of it were discovered in many places around the world.