The tension between the US and Japan heightened because Japan sank USS Panay during its assault on Nanjing and a Japanese soldier also slapped the American Diplomat John M. Allison, US government exerted pressure on the Japanese government. Later the Japanese soldiers in Nanjing apologized to Allison. This incident came to be known as Allison Incident. The US government received many reports about the atrocities of the Japanese Army but the two countries were only focused on safeguarding their national interests.
The Second World War earned the United States a place at the grown ups table because they showed the rest of the world they were not to be trifled with. Both with their troops fighting and the fact that they were able to finish making the atomic bomb before an old, well established country like Russia.
