In re: the “ovens” absolutely true, but several concentration camps with shootings, guillotining etc, and burial disposal, were in place and operational. This being true to the overall US policy in re: the “ovens”, the vast number of camps in operation and the nazi agenda of genocide. This agenda was for all in opposition to the socialist state of Hitler, of whom a majority were Jews, but included Gypsies, Catholics, Lutherans,Jews,Poles, Russians, Ukrainians, Maquis, Greeks, Cypriots, Hungarians, Romanians, etc.
Point taken on Wannsee dating, but long term US policy ignored Jews along with all the rest of the persecuted of the Nazis— it was not the priority and State was filled with snot nosed Eastern academe elitists who carried water for world socialism. And still do today.
Long term US policy was to defeat the Nazi regime. Modern critics have the luxury of knowing when the war would end, something not available to the war planners of that time.
The military assets available to the war planners were being used to defeat the German military as quickly as possible. The camps had no strategic value, most of them were located far to the east of the front lines, and had the rail lines to them been bombed the Germans would simply have rebuilt them.
It’s not clear to me what critics think would have been accomplished by bombing the rail lines. If the camps were cut off the inmates would have just died sooner of starvation. New inmates would have been diverted to new sites, father east, and it would have drawn 88s to the camps since the Germans would be expecting more raids.
And while the death camps are known factor today at that time it would have been impossible to separate rumor from fact. WWI had been filled with stories of the Germans bayoneting Belgian babies. Propaganda and war run together, you don’t have to be cynical to question atrocity stories. The soldiers liberating the camps were shocked to discover what had gone on. If the death camps had been common knowledge they would have been revolted by what they saw but they would not have been surprised.