UPDATE: TSO sends that Obama can deploy the forces without Congressional approval and they would have to then not fund the troops already in theater next Fall during appropriations negotiations. That changes things a little.
OK so I have been mulling this over and have some more thoughts.
My initial reaction is still that naming a date, even with the caveat of "conditions on the ground", is a major mistake.
But what if that calculation was made because the troop increase could not have gotten through Congress without it? That is a reasonable concern. The question then becomes, if that is the only way to get it approved, does the exit date render the troop increase moot or a waste? Maybe.
An announced exit date makes it tougher, perhaps impossible, to get Afghans to partner with us. Why would you stick your neck out and work with us, when the Taliban will still be around when we leave. Even if you think that the conditions exemption means we will stay longer, are you gonna take that risk? I wouldn't.
So is a troop surge worthwhile if the exit date means those troops will likely have fewer partners. And doesn't that make the civilian surge equally tougher? Even with this exit date it will be tough to get Congress to approve this.