"in my opinion is to level with the world and let them know we're in a quandary. Tell them publicly that there simply is no plan with any real chance of success left. Bush needs to fly into Baghdad, get on Iraqi TV, Al Jazeera, and any other media outlets that are watched and listened to heavily by diverse groups and apologize for the failure. He can use whatever justification he needs to feel right about his decisions to invade but ultimately he, and he alone needs to face the "firing squad" in this and try to get America as a country off the hook."

Perhaps this would make you feel good, but I fail to see how this does you any good- therefore it would only serve you emotionally only in short term- until such time as reality again impose itself on your world.
Maybe if Bush was the Son of God this would make some sense. But he is not, and even if he were, it still wouldn't do anything in for Iraq or America in terms of say next decade or two.
We can leave Iraq tomorrow, if we are reckless in terms of what happens to Iraq and happens to America and the world.

Let's look at Korea. We could also end the current division between this N and S Korea. To use your expression, we are on a hook in respect to this situation.
There is nothing stopping us from leaving Iraq, S Korea, Europe, Japan, Tiawan, Kosovo, Afghanistan, etc. What is stopping us from applying this "realism", is the knowledge that we in this world which are interconnected- we doing best to prevent another WWII, but it would be something much worse than WWII and it's possible it will happen regardless of what we do.

Let's look at the Iraq-Iran war. The US policy in regard to the Iraq-Iran war was dominated by "realism" policy: Let them fight this out until they get tired of it and will evenually be forced enter some kind peace agreement that ends the war. The policy was also to contain the war- prevent it from spreading into a broader conflict. The Iraq-Iran war was also in the context of the Cold War- which is simply, what was important was the Soviet involvement and intentions regarding this war. Both Iran and Iraq were "clients" of the Soviet Union.
But it all can be sum up as far as American national security- we didn't care if Iraq and Iran fought and killed millions people.
It wasn't seen within our power to stop it, nor seen in our interest to stop it. Now in terms of miltary power it would not have been within our power to stop it, but it was in our interest to stop- and we could have tried to use soft power and applied pressure on our allies to apply soft power to stop it.
One could look at this way, had Iran still been an ally to the US, the war would have never have happenned.
Had countries in the middle east not been "non-aligned" and had better relations with America, we could have more easily applied pressure and used soft power to prevent war from starting or at least ending it quickier. Had either state had nuclear weapons- we would have been more moviated to find any way possible to prevent/end the conflict.

Many on the left, point to Rumsfeld being as special envoy, as something which is wrong/disgraceful. Which is foolish, what may have been wrong is not having special envoys to Iraq sooner and with more political support for such missions. Had we had diplomatic relations with Iraq, this could also have been effective in preventing or at least stopping the war. And of course obviously we had no diplomat relationship with Iran- by attacking our embassy and abusing it's personnel they committed acts of war in regard to the US.