Preempting A Bad Outcome

Obviously the war on Iraq is not going well. Even Bush and Howard have to admit that. However they are anything but ready to back down. Instead they want to send additional troops to the war-torn country, even though it is not clear whether that will help the situation. It would be unwise to lie to the public, such as telling them "the additional troops will ensure our victory in six months". If such a promise is not delivered in time, the public backlash will be quite unmanageable. So now we often hear the administrations preempting a bad outcome, essentially telling us "don't get your hopes up on this one". I find this strategy flawed. First lowering expectations does not make a bad outcome easier to accept, especially when "bad outcome" means more dead soldiers. The only difference is the level of disappointment, and at this point we are all too numb to be further disappointed. Secondly, telling people a plan is likely to fail begs the question of why implement the plan in the first place? I'll really like to hear the White House's logic on this.