Russia has felt land locked and boxxed in since the 1700's. They fought Sweden (who owned Finland, Estonia and Latvia at the time) and built St. Petersburg on the Baltic to have an outlet to the sea. Then they fought the Lithuanians, Polish, and Ukrainians to acquire more territory. Then the fought the Turks for outlets to the sea along the northern Black Sea coast. They went east to acquire Siberia, and south into central Asia. They have expanded for over 200-250 years. They shrank after the fall of Communism in the Soviet Union and all their conquered territories got their independence. Putin just wants it all back.
Russia refused to remove their troops from eastern and southern Europe after WWII and let their old governments back into power that were there before the NAZI's took them. Poland, Romania, Bulgaria, Hungary, Yugoslavia, Estonia, Latvia, Lithuania and Czechoslovakia. Stalin put puppet communist governments there and kept their troops there until they were well established. We and the Brittish removed our troops almost immediately from Norway, Denmark, France, Italy, Greece, The Netherlands, Belgium, Luxemburg, Italy, and Austria. We only kept troops in Germany to de-NAZIfy it. So when Russia refused to let the pre WWII governments return to power, the west formed NATO, which expanded eastward after the fall of the Soviet Union. The former east block countries absolutely do not want to go back under Russia's thumb.
