US (mostly) lets Iraq form its cabinet (csmonitor.com, 04/28/05). This is a great article on how the U.S.' past meddling with Iraq is impacting the ongoing efforts to form an Iraqi government, though it doesn't put it that way.
It describes current meddling - phone calls, political pressure, chiding from Condi.
It describes past meddling, though not in enough detail to make it clear that the current interim government is set up based on rules laid out by the U.S., and the inherent weakness of using a U.S. structured system to prevent majority rule is complicating the government's legitimacy.
It mentions that "government by the numbers," the factionalized system inherited by the U.S., may result in years of instability. It even mentions that historical U.S. support for the Kurds is complicating negotiations by allowing the Kurds to bargain out of proportion to their numbers, confident in U.S. backing.
I am not saying that proportional representation is an evil thing: I'm saying it's going to be difficult to legitimize because it was imposed by a self-interested foreign power with a minority ally. I'm saying it's unusual among democracies, which complicates its acceptance by majorities who will experience minority veto. I'm saying it raises questions about why different groups forced together by the British years ago must be forced to act as one nation now, even though some groups (most notably the Kurds) want their own country.