Why was modernisation of the Soviet Union necessary for Stalin?

Modernising the Soviet Union was important for a number of reasons, primarily the need to prove communism was a viable and strong form of government in the eyes of the Western world. As the first nation to fully commit to a socialist government, Stalin needed to prove that Russia could be as much of a trailblazer as the West when it came to social, industrial and military development in order to dispense the idea continually projected in the West that communism could only lead to destitution and poverty. Whether he was successful in proving this throughout his term or not, it was necessary for Stalin to at least project the idea of a modern, Soviet state. This would convince any visiting dignitaries that the Soviet Union was an attractive place to live which was able to thrive without the need for a capitalist regime. It would allow Stalin to present the Soviet Union as a country that was valid in the eyes of other world governments (especially in the face of the ultra-capitalist United States). This was especially important since Russia had already been perceived as laughably backward for the past 50 years, primarly due to the failure of the Tsars to modernise and Westernise, which had almost certainly contributed directly to their recent humiliating military defeats. Due to the failures of the Crimean War, the Russo-Japanese war and World War One (until 1917), Russia had been viewed as a highly backwards country that desperately needed to modernise militarily and industrially. Stalin, therefore, did not just need to modernise Russia's military and industry in order to prove himself as a leader, he needed to prove that the previous (autocratic and capitalist) regimes before him were unfit to have come before the Bolsheviks. Most importantly, however, he needed to prove that Russia's days of failure were coming to an end with the new socialist regime, as this modernisation would bring the Soviet Union back into competition with the rest of the globe's leading nations. Stalin's 'true' motivations towards the modernisation of the Soviet Union could be endlessly debated, but it certainly appears that his primary goal for modernisation was to provide the illusion that the old days of defeat for Russia were over; they were now the thriving, socialist Soviet Union, the liberators of Paris during World War Two, capable of self-sufficiency without the need to rely upon capitalist nations for aid. Whether this highly propagandised image was ever met can certainly be disputed, but Stalin's projections to the rest of the world during his modernisation of industry, agriculture and the military appear to confirm the necessity of modernisation in order to project the best possible image of a socialist, modern, independent Soviet Union.