Explanation: The atomic bomb was developed and assembled under the presidency of Franklin D. Roosevelt during the time of the second world war.
Once they were ready, 2 bombs were deployed by the US Army against Japan. The first bomb was detonated in Hiroshima on August 6, 1945, and the second was detonated 3 days later in Nagasaki. Due to the great impact that the bombs caused, Japan signed its surrender.
At the time, it was thought that due to the immense destructive power of the bombs, no other global conflict would start.
Although numerous conflicts have occurred since the end of World War II, there has not been a conflict on a global scale til this day.