What caused the popular uprising was the disastrous state of Russian economy by then, with rampant inflation and the complete breakdown of food supply to the cities, not military defeats; what these defeats had done was to undermine the reliability of the army as a repressive force as many regiments sided with the rebelllious mobs instead of shooting them as they'd done in 1905. But even that was not a new phenomenon, even in 1905 the reliability of many army units had been put into doubt, and in order to crush the revolution in Moscow it was necessary to send there by rail several regiments of the Imperial Guard from Saint Petersburg. Alas, by February 1917 the Imperial Guard regiments had been squandered in fruitless attacks against German positions in Volhynia, and the survivors were not in the mood to act as the Tsar's firefighters anymore.