In the mid-years 30. XX century, Workers 'and Peasants' Red Army (RKKA) as assessed by the Polish general Stachiewicz, “stands out for the greatest military power in Europe”. It was indeed so. In time, when he spoke these words, The Red Army was the strongest in numbers and best equipped with technical equipment in the world. A frightening number 170 divisions supported by more 20 000 tanks and 15 000 planes was enough, to discourage anyone from going to war with the Soviet Union.
However, contrary to appearances, The Red Army was not a very formidable opponent in combat. Despite the breathtaking numbers, they did not reflect the actual military potential of the Soviet armed forces. 170 the Soviet divisions were actually a mass of untrained soldiers, who joined the army in search of a life better than their farm. Their uniforms were often incomplete, military jackets were replaced by ordinary cotton jackets, a i karabiny, or guns, they wore on strings, the number of cartridges he possessed was not sufficient to carry out longer fights. Soviet soldiers could not fight, and their only advantage on the battlefield was their number.
The military equipment of the Red Army also left a lot to be desired. The tanks were actually outdated machines, whose modernity was more or less on par with the Polish. It was the same with airplanes. also, the Soviets did not use any doctrine, enabling them to achieve a brilliant victory. Furthermore, showed a complete lack of skills in using the new war technique, throwing tanks, infantry and planes at the same time to fight, like spilling them out of a huge sack (this method was the main cause of the defeat of the RKKA during the war with Finland).
A knockout blow, which Stalin himself inflicted on the Red Army's combat capabilities were the purges carried out in 2. mid years 30, that is, shortly before the outbreak of the war. As a result of the fear-induced liquidation of possible political enemies, that could threaten Stalin's dictatorship, murdered, more than deported or arrested 50 000 officers, including the current one, the actual commander of the Red Army, Marshal Michael Tukhachevsky. This had a significant impact on the strength of the Soviet armed forces, thus deprived of experienced officer cadre. The weakness of the Soviets came to light drastically during the border battles with the Japanese at Lake Chan in 1938 year, when the much weaker numbers of Asians were dismantling large Red Army units.
With such a state of affairs, the Soviets would never have dared to attack Poland on their own, knowing, that they would pass judgment on themselves, sending armies for some destruction. The defeat on the Vistula with 1920 year. That is why they made the aggression in cooperation with the Germans and that with 2 and a half weeks late, which guaranteed them, that the Polish Army is so weakened, that he will not put up much resistance, because in that way it would have exposed the Red Army to ridicule, in the eyes of foreign observers.