The empire’s stability

Tsar Alexander III once said that Russia had only two real friends: its army and its navy. Did Russia’s military contribute positively to the empire’s stability or longevity or, conversely, did its failures ultimately lead to imperial Russia’s downfall? Be sure to give specific examples and consider the causes and effects of changes in Russia’s military over time, including its composition, training, preparation, the strategy or tactics of leaders, composition of the officer corps, the role of individual rulers, technological changes, economic constraints, the “paradomania” phenomenon, overall popular patriotism or lack thereof, or any other factors you find significant.