Originally Posted by Guest

Did America only become the world's most powerful nation after World War II? - Quora

"Britain was obviously the most powerful nation on earth in terms of standing military power until the 1930's when Germany surpassed her."

"Britain probably remained the most powerful nation on earth until World War I"

"That said, the second point is about standing industrial might, and Britain was probably passed by Germany in 1935. Both Germany and Britain were likely passed by the US at the outbreak of WWII (1939). While the US remained out of the war for two years, the US nonetheless started arming herself. At that point, the factories began retooling for war, the military grew in power and the US became--and has not since given up--the most powerful military forces on earth."