A friend of mine points to this column as possible evidence that WFB supported the surge. Here’s how it concludes:

Here Congress, using the judgment of its own members, needs to tax itself in order to vote not its conscience, exactly. To vote to sustain the huge effort we began in 2003 when the executive — ambiguously encouraged by the legislature — decided on war. Those members of Congress who, if they had it to do again, would vote as they did before could swell the ranks of the Libertarian party.
U.S. elections are around the corner. And there are voters who are not persuaded by the analysis of Ambassador Crocker, or those of American newsmen. And this is of course the final branch of government: the voters. The critical questions in the halls of Congress: Will they understand if you do? And if you don’t?
If the vote were mine, I’d say: Stick it out. You can’t, by doing so, be accused of thoughtlessness, certainly not of perfidy.

Pro-surge? Certainly not anti-surge.