Source B was written on August 6th (the day of the bombing) by one of the airmen in the squadron that bombed Hiroshima. Despite not being on the Enola Gay, this man was an eyewitness to the massacre, and when the letter was written the event was still fresh in memory, which leads me to believe that any factual information within will not be clouded by time; in other words reliable. However the source does not contain much factual information and is instead plentiful in political spin and sounds like it could have been penned by a White House speechwriter:
“…tempered with hope that this terrible weapon…may…prevent further war.”
We cannot even be sure this ‘letter’ was actually written by a man for his son, assuming it was though, it probably and accurately reflects the mood and opinion of any optimistic American at the time.
It may be overly cynical and sceptical to believe the letter was intended for publication, it was probably written, as it claims it was, by a US Airman. The man’s tone is calm and I don’t think he would lie to his own son. Therefore, I believe the source is reliable in conveying the American outlook on the event, but it has to be questioned if this was what was really written by the man and not edited by a military censor.
Source H was written by a Sunday Times journalist with a British prisoner of war that was working in a Nagasaki dockyard on August 9th. This man was an eyewitness, just half-a-mile from ground zero, and I believe his account of the effects of the bomb would be reliable and hard to forget, however, it was written 42 years after the event and, consequently it could be prone to error.
This excerpt is mostly a factual account of the conditions on the ground and the latter section is of the piece describes how he personally felt on the day. It is not propaganda and there would be no point in lying about how he felt anyway. Even after 42 years, I do not believe that he would have forgotten his emotions on such a significant day, the purpose of the piece is to inform and describe and I would take what is said as true.
I am of the opinion that both sources are reliable but more so source H. source H was to inform and describe the events to people, largely, in the generation after the bombing, source B was to influence contemporary peoples’ opinion and it seems to be less believable.