The United States detonated two nuclear weapons over the Japanese cities of Hiroshima and Nagasaki on August 6 and 9, 1945, respectively, with the consent of the United Kingdom, as required by the Quebec Agreement. The two bombings killed between 129,000 and 226,000 people, most of whom were civilians, and remain the only uses of nuclear weapons in armed conflict.
Innocent people died because United States wanted to try atomic bombs. Unites States is still proud of its act and never apologized for killing thousands of innocent people. The two bombed cities were destroyed and people who survived were heavily injured and became homeless.
United States, Russia, United Kingdom, France, China, India, Pakistan, Isreal, and North Korea are current countries that store near 14000 atomic bomb warheads. If an atomic war happens, these countries can easily destroy the earth and every single person in it.
Atomic bombs are a global threat to humanity and will in no way guarantee peace. No country should have the tools of mass murder and destruction for any reason.