Why was the novel doctor zhivago banned?

Somewhat negative characterization of the Russian Red Army and the intelligence agency. it is hinted Zhivago"s brother is an officer in one or the other, the two men, who meet at a field hospital- a sort of wagon-train of horse-drawn ambulances, well have a sort of spat. Adultery - a conflict of females between Zhivago"s wife and his mistress Lara or Laura erupt. Interestingly Laura or a Word spelled very similar to it in Russian means, literally encampment or garrison . Laura plays the field!