Should Truman not have first demonstrated to the Japanese the power of the A-bomb?

The actual (post?) WW2 real reason was that there wasn't enough time - They needed to move quickly to force a surrender from Japan.

With the Germans defeated, the Soviets were building forces in the East and preparing advances on Japanese held territories. The Americans knew the Soviets would take Japan by conventional force quicker than they could build up enough forces in order to beat them to it.

Therefore it was imperative to get a surrender from the Japanese before it fell under the communist curtain and extended soviet influence even further in the area. The only way they could do this was by using the bomb.

All is fair in love and WWII.

Thanks to you yanks for saving the Brits, French, Italians, Russians, entire world. They couldn't do anything right without you.

There's an argument that the fire bombing of Tokyo was more apparently destructive than Hiroshima and Nagasaki, and that one of the factors that led to the Japanese surrender was the threat of the USSR turning its war machine against Japan.

It seems you’re projecting onto him, which you have ne evidence, all these petty reasons for Truman’s decision to fulfill his Commander-in-Chief duties. Even save American lives.

This film shows lengthy ponderous chats analyzing every aspect of discussion—every point of view, strategically and morally, and I have no reason the conclude that it was glossed over in real life by Truman, the mushroom-cloud-laying motherfucker, that you are trying portray him as.

The Imperial Japanese of this time period were a brutal enemy. They killed our boys at Pearl, in a sneaky-as-shit preemptive attack, and their corpses are still there floating in that harbor behind degraded (supposedly once-watertight) hatches. We were even isolationists then, and they still drew us into combat! Poked the sleeping dragon like a petulant child. Japan attacked Australia and Indonesia the same way. Our conventional bombing of Tokyo and coastal military targets had already been far more devastating, with no sign of their surrender. Rape camps for Chinese woman prisoners, Kamikaze pilots, a militarized civilian population. They were a mess. Nearly the ISIL (ISIS) of their time.

Japan had a troubled juvenile history, and we straightened them out with some tough love, and now they’re a straight ‘A’ student.

The people of Hiroshima were warned, the US dropped thousands of leaflets on the city warning them to evacuate as mass destruction was imminent.

Japanese did not believe it. In fact theres a funny story of a survivor of the first bomb returning to his home town and the people tell telling him hes full of shit when he tried to tell others what happened.