This is interesting, given how Putin often seems to be nostalgic for the glory days of the Soviet empire:

Yet Putin also struck a conciliatory note with Poland – a former Soviet satellite-turned European Union member – saying that the grief caused by the 1940 murder of more than 20,000 Polish prisoners of war by the Soviet NKVD struck a cord with the average Soviet citizen, who also suffered under totalitarianism.
“To the people of Russia, whose fate has been deformed by a totalitarian regime, the sensitivity of Poles over Katyn, where thousands of Polish soldiers lie, is well understood,” Putin wrote in what appeared to be an unusually strong criticism of the Soviet government from him.