i'd like to add another motivation in favour of bombing the camp:
if the allies had bombed aschwitz then all the nazis involved in the industrial extermination process would have got a clear message from the allies: "
we KNOW what you are doing and when it's all over you will be accountable for this"
On the contrary, the fact that no military action was ever taken against any extermination camp made many nazis think that the allies ignore what was going on. Many people working in death camps felt somehow safe, far away from war front, just waiting for the end of the war. they believed that dismatelling the camp a few weeks before the allies arrival would be enough to hide everything.
I heard this argument when i visited the camp, actually i never thought about it earlier.
Btw, I strongly suggest everyone to visit the aschwittz/birkenau camp. For european people it's very easy and cheap. just take a low cost flight to krakow (skyeurope).
Auschwitz is really impressive, the explanations are good and you learn about everyday life in the camp, including the life of the nazis there. But when you move to birkenau the effetct will be even worse, even though in birkenau there is hardly nothing left, just the railway and a few barracks (here is better to hire a guide). What really strucks you is the vastness of the camp, it's huge, enourmous. being there and figure out the death-factory fully working is something rather disturbing.
PS: when your visit is over ther's only one way to reconciliate yourself with mandkind: enjoying krakow nightlife!! girls there will make you forget all the horror you saw before
well, at least for one night........