Link to an article by V.I. Lenin:
It seems like one thing Lenin fails to mention about Leo Tolstoy is his remarkable ability to craft psychologically consistent characters. There are few writers capable of such deeply realistic characters as Tolstoy. And yet, Lenin’s point is essentially that the steadfast commitment to realism is what dooms Tolstoy in a political sense, in that his failure to step outside descriptive portrayals through realism means that he never really explores potentialities and never really challenges the status quo.
But in another article Lenin made his most basic criticism of Tolstoy, which seems apt:
“Tolstoy reflected the pent-up hatred, the ripened striving for a better lot, the desire to get rid of the past—and also the immature dreaming, the political inexperience, the revolutionary flabbiness. Historical and economic conditions explain both the inevitable beginning of the revolutionary struggle of the masses and their unpreparedness for the struggle, their Tolstoyan non-resistance to evil, which was a most serious cause of the defeat of the first revolutionary campaign.”