I believe that Kerry should respond in kind to Bush's attacks that he has been "switching" and "shifting" his position on Iraq.
I think Kerry should throw the ball back into Bush's court with exactly this same charge. He should just point out that if anyone has "switched" or "shifted" positions on the Iraq war - it is actually Bush who's been doing the "shifting" - by "changing" the reason for going to war!
Ever since the before the war, Bush has been all over the place with so many different reasons for going to war. And when one charge is proven false, he just changes it to the next one...
Here is little list of reasons Bush has given so far:
1) Saddam was involved with 9/11
2) Saddam "has" WMD
3) Saddam is "developing" WMD
4) Saddam "wants" to develop WMD
5) Saddam wont cooperate with the inspectors
6) We can't trust the weapons inspectors
7) Saddam is just "bad"
8) We need to liberate the Iraqi people
9) We need to "Remake" the middle east
And the list goes on and on....