1) "Isolation Siege." In this scenario, U.S. and coalition forces would cut Baghdad off from the rest of Iraq and slowly degrade its communications and military infrastructure with airstrikes and limited ground-level assaults. Success would depend on the demoralization of those holding the city. It was apparently the least costly option for U.S. forces but very costly for the civilian population. The scenario would "definitely include turning off the lights," according to a note attached to the presentation.

2) "Remote Strike (Rubblizing)." This is a violent scenario that relies on overwhelming airpower. The presentation does not mention the costs to the civilian population. But under this option, a robust air attack would hit most sections of the city—and be designed to break the back of any and all resistance in Baghdad. The briefing did not note whether U.S. and coalition forces would employ precision or pinpoint bombing or employ a more general urban bombardment.

3) "Ground Assault, Frontal." The briefing was far more specific about this scenario than any other, perhaps because this alternative requires the most logistical coordination, much of which is detailed in the PowerPoint presentation. It notes the number of troops that might be needed and how they ought to be deployed. We're not going to share these details, out of concern that could lead to troops being put in harm's way. But the name of this option said it all: U.S. forces would enter the city, identify strongholds of military resistance, and assault them in block-by-block and house-to-house fighting. This would entail "a linear sweep across the city." Clearly, this would be the most costly to U.S. troops and the most difficult course of action, but the briefing did not address that or the collateral damage that might ensue. Neither did it specify the kind of units U.S. and coalition forces might be facing—or the likely level of resistance that those forces would offer.

4) "Nodal Isolation." Under this option, mainly air forces (and maybe some ground troops) would "isolate" communications and command nodes in the city by destroying them. The goal would be to make resistance in Baghdad virtually useless by separating the assets of Saddam Hussein's regime from the civilian population. The planners did not envision the use of large amounts of combat troops for this scenario. But they apparently did not factor in the possible presence of Saddam's irregular units and the paramilitaries' ability to maintain and enforce the regime's authority.

5) "Nodal Capture." Instead of blasting apart the communications and command nodes, U.S. forces would try to secure these points. That would leave the government infrastructure intact, presumably to save it for use in a post-Saddam era. The scenario did not detail the types of combat units to be used in carrying out this difficult mission, but they likely would include U.S. Rangers, Delta, special forces, and British SAS teams.

6) "Segment and Capture." In this modified version of an overland, frontal assault, specific neighborhoods and areas of Baghdad would be identified and assaulted by air and ground operations. The briefing contains explicit ethnic and demographic details of Baghdad's neighborhoods, apparently to help commanders decide which sections to attack first and which parts would most likely welcome U.S. and coalition troops. But picking off one area at a time could be a long, drawn-out endeavor, not all that unlike the siege option.