At the end of June 1944 Auschwitz was operating at full capacity. Trains were arriving from Hungary every day and the process of killing and cremating the victims was as efficient as it had ever been. By now the Allies had substantial evidence that thousands of people were being murdered every day.
By mid June 1944 Roswell McClelland, the U.S. War Refugee Board representative in Switzerland, had received the report written by Auschwitz escapers Rudolf Vrba and Alfred Wetzler. The report arrived in Washington on June 16, about a month after Auschwitz started receiving the Jews from Hungary. It was one of the catalysts for the first firm proposal for the Allies to bomb the camps. The proposal to bomb Auschwitz – Birkenau was made by Benjamin Akzin, a junior member of the U.S. War Refugee Board on 29th June 1944:
In view of the preeminent part evidently played by these two extermination camps in the massacre of Jews, equipped to kill 125,000 people per month, it would seem that the destruction of their physical installations might appreciably slow down the systematic slaughter at least temporarily.
The methodical German mind might require some time to rebuild the installations or to evolve elsewhere equally efficient procedures of mass slaughter and of disposing of the bodies. Some saving of lives would therefore be a most likely result of the destruction of the two extermination camps.
Though no exaggerated hopes should be entertained, this saving of lives might even be quite appreciable, since, in the present stage of the war, with German manpower and material resources gravely depleted, German authorities might not be in a position to devote themselves to the task of equipping new large-scale extermination centers.
Aside from the prevenve signicance of the destruction of the two camps, it would also seem correct to mark them for destruction as a matter of principle, as the most tangible — and perhaps only tangible — evidence of the indignation aroused by the existence of these chamel houses. It will also be noted that the destruction of the extermination camps would presumably cause many deaths among their personnel—certainly among the most ruthless and despicable of the Nazis.
It is suggested that the foregoing be brought to the attention of the appropriate political and military authorities, with a view to considering the feasibility of a thorough destruction of the two camps by aerial bombardment.
It may be of interest,in this connection, that the two camps are situated in the industrial region of Upper Silesia, near the important mining and manufacturing centers of Katowice and Chorzow (Oswiecim lies about fourteen miles southeast of Katowice), which play an important part in the industrial armament of Germany. Therefore, the destruction of these camps could be achieved without deecting aerial strength from an important zone of military objectives.
Presumably, a large number of Jews in these camps may be killed in the course of such bombings (though some of them may escape in the confusion). But such Jews are doomed to death anyhow.The destruction of the camps would not change their fate, but it would serve as visible retribution on their murderers and it might save the lives of future victims.
It will be noted that the inevitable fate of Jews herded in ghettos near the industrial and railroad installations in Hungary has not caused the United Nations to stop bombing these installations. It is submitted, therefore, that refraining from bombing the extermination centers would be sheer misplaced sentimentality, far more cruel than a decision to destroy these centers.
Even amongst those concerned with the rescue of the Jews the proposal was controversial. It was argued that such raids would allow the Nazis to claim that Jews had been killed by Allied bombing. The military were to reject the proposal on practical grounds – it would be difficult to achieve accurate bombing and that in any event the Germans were adept at repairing bombed railway lines.