ljadw wrote:1) It is obvious that the SU was economically stronger than Germany : it produced more tanks,artillery,aircraft,oil,etc
On the contrary, every piece of evidence indicates that Germany was ahead of the USSR economically and industrially. The basic inputs of the industrial economy, coal and steel, were overwhelmingly in Germany's favor:
Germany: 268,595,000 tons of coal and 28,744,000 tons of steel
USSR: 75,536,000 tons of coal and 8,069,600 tons of steel
Germany: 273,895,000 tons of coal and 30,603,000 tons of steel
USSR: 93,141,000 tons of coal and 8,474,800 tons of steel
Germany: 250,837,000 tons of coal and 25,853,000 tons of steel
USSR: 121,470,000 tons of coal and 10,886,700 tons of steel
This data obviously begs the question "Why then was the USSR overwhelmingly ahead of Germany in military output?", which was your reply to my initial assertion that Germany was ahead industrially. The short answer is that the USSR never outproduced Germany in military equipment, and that the usual yardsticks (i.e. tanks, guns, etc.) on which such an assertion is based are fundamentally flawed.
To compare Germany's military output to that of the USSR, we must first clarify what, exactly, is "military output". For the Germans, "military output" amounted to the following categories of equipment:
Ammunition, common equipment, tanks and half-tracks, railway cars and locomotives, automobiles, aircraft (and Luftwaffe-related various outputs), artillery and small arms, ships, electrical equipment, sea mines and torpedoes, explosives and, finally, precise mechanics and optics.
In 1942, Germany's military production consumed 45.7% of the steel supply (14,043,000 tons), in 1943 52.7% (16,368,000 tons) and in 1944, 53.7% (15,378,000 tons). Note that Germany's steel supply was slightly larger than it's steel output, since it imported finished steel from occupied nations, mostly France and Belgium.
This page gives a detailed breakdown
of Germany's military steel consumption in 1943. As you can see, "big-ticket items" like tanks, artillery and small arms constituted a relatively small part of it, respectively 12.1% (tanks and half-tracks) and 7.4% (artillery and small arms). It also helps to understand the comparatively larger Soviet output in some limited categories, the most obvious of which is tanks.
It is well-known that the USSR outproduced Germany in AFVs during the war. Here's a quick comparison of AFV output from 1942 to 1944, data being Germany / USSR:
1942: 6,180 / 24,640
1943: 12,063 / 24,092
1944: 19,002 / 28,983
At first sight it looks like the USSR's industry is dwarfing that of Germany, especially in 1942. But what is a tank, if not another ground vehicle? This qualification is especially appropriate given that associated heavy industries like the automobile industry or the rolling stock industry can quickly be converted for AFV production, as demonstrated by the Soviets between mid-1941 and early 1942. As shown here
, the Gorky Automobile Factory, for instance, converted a large part of it's floor space for the production of light AFVs like the T-60, T-70 and SU-76, of which it produced a total of 13,791 between 1942 and 1944 (63% of the Soviet total). No. 112 Factory, which mainly produced locomotives before the war, turned out 9,188 T-34s over the same period (21%). And Uralvagonzavod, which produced railway cars, was merged with KhPZ to form No. 183 Factory, which turned out 21,571 T-34s between 1942 and 1944, amounting to 50% of the total.
Thus, if one wants to compare German and Soviet output, one has to compare whole categories together, and not just a limited cross-section. Thus, "ground vehicle production" actually looks like this, data again being Germany / USSR:
Tanks and SP guns: 6,180 / 24,640
Armored cars: 982 / 2,623
Half-tracks: 10,152 / 0
Trucks: 81,276 / 30,947
Cars: 27,895 / 2,567
Locomotives: 2,637 / 9
Train cars: 60,892 / 147
Tanks and SP guns: 12,063 / 24,092
Armored cars: 806 / 1,820
Half-tracks: 16,964 / 0
Trucks: 109,483 / 45,545
Cars: 34,478 / 2,546
Locomotives: 5,243 / 43
Train cars: 66,263 / 108
Tanks and SP guns: 19,002 / 28,983
Armored cars: 485 / 3,000
Half-tracks: 17,143 / 0
Trucks: 89,069 / 53,467
Cars: 21,656 / 5,382
Locomotives: 3,495 / 32
Train cars: 45,189 / 13
"Ground vehicles" consumed 18.5% of Germany's total steel supply in 1943, and 34.4% of the military's share. The second largest steel user was ammunition, which consumed 11.6% of the total supply and 21.6% of the military's. In ammunition, as in ground vehicles, Germany was substantially outproducing the USSR, even in 1942
So there you have it: Germany was outproducing the USSR at every point during the war, which makes sense given the large disparity in industrial inputs between the two countries. Only by looking at a limited cross-section of military outputs, and thus misleading data points, can one reach the conclusion that the USSR was economically / industrially ahead of Germany.