It makes no difference if we feel that Saddam's death "diminishes me". Sorry, John Donne doesn't fit here.

What matters is if the Shiite government now feels it is freer to make concessions to Sunnis--like more meaningful action in purging Shiite militias from the police---an absolutely essential step in ending violence in Iraq.

Maybe the government will feel freer to to do this, maybe not. But clearly the danger of any coup to re-install Saddam is now gone. So the government should in fact do it. I would think that even Sadr's people should now feel less threatened than before.