I just don't see a Democratic Congress going into a government shut-down style confrontation with Bush over funding, though, so you've got the same veto problem on funding as you do on the authorization. Am I missing something? I don't think we could depend on Bush accepting funding cuts.
But, if you concentrate the debate on the pure policy aspects of ending the war in Iraq, you can keep increasing the pressure because there's no way the Republicans even come close to winning that debate. They may be able to stall it, may be able to keep the war going, but they will absolutely get hammered in 2008 if they do. If you focus on funding, then the Republicans can muddy the waters with the "taking money away from our troops" message. The GOP is desperately trying to get that debate going rather than the pure policy one.
To me, you've got the same chances of success with both (veto-proof majority being the goal), but the authorization angle is far superior politically.
The difference between funding and authorization is that funding is an annual requirement - the authorization in H J Res 114 needs no topping up every year, but the DOD coffers do.
Defunding requires the Dems to trigger a constitutional crisis in which they bet the farm that they can win.
Which is pretty much like Russian roulette with one empty chamber.
The 08 election is a whole different kettle of fish: acting now to set up a record to run on is sensible. Hopefully, the Dems get a trifecta out of it.
But, realistically, there's nothing doing until then. Not much, at least.
To me, the one-off nature of the authorization resolution is a positive feature. Basically, it's a stand-alone political fight, unencumbered by any extraneous details involving troops, Pentagon lobbying for funding, or anything else. Defunding is a messy thing, and I think the Democrats should avoid messy, if possible. Keep it simple and easy to understand. You may not have the numbers to pull it off in the Senate, and if so almost surely won't have the numbers to override the veto, but there it is. That's reality. But this has the best chance of success, imo, and by far the least downside of any approach.
Meanwhile, while the fight over actually continuing Iraq is confined to that one vehicle, you can use the funding mechanisms to go after other things, like the unbelievable corruption and profiteering that has, among other things, gone to fund the political establishment of the right-wing.
Just noticed an inconsistency in my last two posts in the chance of success. What I meant in the first is that you have the same target for success of both approaches (a veto-proof majority), but, as I mention in the second, you have a better chance of reaching that with the de-authorization approach. It's still not much of a chance, admittedly, but it's at least better than going after funding.