I don't recall any mass genocide in any first world Western Democracy, since the Nazi's in Germany.
Stalin was a left wing Authoritarian, as was Mao. Authoritarian dictators on both sides of the political spectrum, are responsible for the world's genocides and mass murderers, and that includes Netanyahu's treatment of the Palestinians.
Netanyahu tried an authoritarian takeover of the Israeli government, by strippping the Supreme Court of power, and Israeli's revolted. That's when Hamas struck - helping to keep Netanyahu in power. They saw him as endangered and weak and attacked.
No people has lived well under an authoritarian dictator - on either side of the political spectrum. Castro and Cuba anyone? Russia is failing. Hungary is failing. North Korea.