Should the U.S. draw down to a non-combat presence of 50,000 troops by the end of August? The answer depends on the purpose of the U.S. presence and what problem it's meant to solve. The Balkan experience offers some useful insights.
Like Iraq, the Balkans suffered intense ethno-sectarian identity warfare which was ended by negotiated settlement (Dayton and U.N. Security Council Resolution 1244 in the Balkans, the Sons of Iraq and Mahdi Army ceasefires in Iraq). Neither Balkan settlement caused the wartime fears and hatreds to simply vanish. But the deals that ended the Balkan wars were accompanied by large foreign peacekeeping deployments that enabled the former rivals to tolerate one another in spite of their fear.
Bosnia, for example, began with 54,000 peacekeepers in 1995; Kosovo began with 50,000 in 1999. These large initial deployments eventually came down: Bosnia today has peacekeepers, but less than 2,500; Kosovo is now down to fewer than 10,000.