Bush and pals have gone nuts in the last week because they've been accused of deliberately misleading America into war with the WMD and Al Qaeda allegations. I think the way to respond is to draw the Republicans out on why this issue is so important. How about saying:
"You're right to be so upset about being accused of something so awful. After all, Republicans, surely you agree that misleading America into a war is an impeachable offense. Let's settle how serious the charge is, figure out who's right and who's not, and take appropriate action against the side that's wrong, whoever it may be."