The latest by Andrew F. Krepinevich, Jr. is worth a whole read, so I'm only excerpting the summary:
Because they lack a coherent strategy, U.S. forces in Iraq have failed to defeat the insurgency or improve security. Winning will require a new approach to counterinsurgency, one that focuses on providing security to Iraqis rather than hunting down insurgents. And it will take at least a decade.
The history and strategy for stabilizing Iraq is there for the taking. Bush spoke indirectly about the oil-spot strategy (noted here), but as with many other aspects of this war, it's been poorly executed and communicated. Krepinevich spoke of the winning "hearts and minds" in three key areas. No less important is an effective campaign for ratifying a fairly decent constitution this coming October (Mark Steyn touches on it here). When Donald Rumsfeld appears before the Senate Armed Services Committee, the second thing Senator John Warner should ask the Defense Secretary is what steps our armed forces are taking to implement this time-tested military/political strategy (it even worked in Vietnam, until it was abandoned). The first thing Warner should ask is for Rumsfeld's resignation.