The collapse of the Soviet Union in 1991 reversed a process that had been under way since the Russian Empire's emergence in the 17th century. It was ultimately to incorporate four general elements: Eastern Europe, Central Asia, the Caucasus and Siberia. The St. Petersburg-Moscow axis was its core, and Russia, Belorussia and Ukraine were its center of gravity. The borders were always dynamic, mostly expanding but periodically contracting as the international situation warranted. At its farthest extent, from 1945 to 1989, it reached central Germany, dominating the lands it seized in World War II. The Russian Empire was never at peace. As with many empires, there were always parts of it putting up (sometimes violent) resistance and parts that bordering powers coveted -- as well as parts of other nations that Russia coveted.
The Russian Empire subverted the assumption that political and military power requires a strong economy: It was never prosperous, but it was frequently powerful. The Russians defeated Napoleon and Hitler and confronted the far wealthier Americans for more than four decades in the Cold War, in spite of having a less developed or less advanced economy. Its economic weakness certainly did undermine its military power at times, but to understand Russia, it is important to begin by understanding that the relationship between military and economic power is not a simple one.
Economy and Security
There are many reasons for Russia's economic dysfunction, but the first explanation, if not the full explanation, is geography and transportation. The Russians and Ukrainians have some of the finest farmland in the world, comparable to that of the American Midwest. The difference is transportation, the ability to move the harvest to the rest of the empire and its far away population centers. Where the United States has the Mississippi-Missouri-Ohio river system that integrates the area between the Rockies and the Appalachians, Russia's rivers do not provide an integrated highway to Russia, and given distances and lack of alternative modes of transport, Russian railways were never able to sustain consistent, bulk agricultural transport.