The military purges must be distinguished from other forms of political terror in the 1930s: an investigation by the Party in the Khrushchev era established that the order for the military repression came from the top and used patently fabricated evidence. To this day, the rationale for the military purges remains a mystery. One theory holds that Stalin—misled by what had happened in the Spanish Civil War—had come to believe that Tukhachevskii’s expertise was dispensable. Another is that Stalin sought to check signs of excessive independence within the military, signs that had become visible as far back as the ill-fated Seventeenth Party Congress in 1934. And some believe that Stalin feared Tukhachevskii’s popularity, seeing him as a potential rival. In any event, the purges slowed down when the ‘Winter War’ of 1939–40 with Finland exposed the weaknesses of the Red Army. Certain officers (including such gifted leaders as K. K. Rokossovskii) were released from the camps and reinstated. None the less, on the very eve of the war, three-quarters of Soviet commanders had been in their posts for less than a year. And at the highest echelons, the Red Army was led by talentless sycophants and overrated cavalry men from the civil war era.
Another weakness had to do with doctrine and planning. For a variety of reasons, the Soviet leadership believed that a war with Germany would most likely start after an extended period of crisis, which would give the Red Army time to mobilize. Thus a formal declaration of war would be followed by a brief defensive phase, in which Soviet forces would check and repel the invader near the frontier; the Red Army would then open an offensive into Central Europe. Thus, Soviet military and political élites presupposed a short war, largely fought on the enemy’s soil; they paid little attention to the possibility that the war might become protracted, that it might require the USSR to organize a defence in depth.
The relative de-emphasis on defence also had implications for frontier fortifications. Whereas the Soviet Union possessed a considerable network of these in 1939, expansion by 1941 (as a result of the annexation of the Baltics, eastern Poland, and Bessarabia) had pushed the frontier 150 to 300 kilometres to the west. Work on new lines commenced in 1940, but procrastination and disorganization slowed progress. In February and March 1941 the Soviet command decided to cannibalize existing fortifications in order to build the new ones. The result was that
Finally, the greatest blame for the ruinous start to the war must rest with Stalin himself. After the signing of the Ribbentrop–Molotov Pact in 1939, Stalin had constructed a foreign policy based on co-operation and collusion with the Nazis, evidently hoping that they would exhaust themselves in a lengthy war of attrition against the French and British. This delusion vanished with the fall of France in 1940. Although Stalin thereafter came to believe that an armed confrontation with Germany was unavoidable, he none the less supposed that Moscow—not Berlin—would determine its timing. After all, it was unlikely that Hitler would turn east while Britain remained unsubdued. In the spring of 1941, although Stalin permitted the mobilization of some of the reserves, he insisted that war with Germany would not come until the following May at the earliest. He therefore saw Hitler’s massive military build-up of 1941 as the prelude to negotiations, not war. From Stalin’s perspective, the only real danger was that war might break out accidentally; it was to guard against this contingency that Stalin was so determined to avoid ‘provoking’ Hitler. That is why Stalin disregarded G. K. Zhukov’s advice (May 1941) to launch an immediate preventive attack to disrupt the concentration of the German army, as well as that of S. K. Timoshenko, whose frantic request to transfer forces from the interior to the border was not approved until June. In a very real sense, Stalin’s miscalculations foreordained the military surprise and devastating consequence of the invasion.
