Rudy Giuliani dropped by a New York firehouse on Tuesday with his good buddy Mitt Romney to deliver some pizza and political wisdom: like this, via Politico's Roger Simon: "I think [Obama] using 9/11 as a source of negative campaigning was a mistake."

The former Mayor was weighing in on the debate over Obama's campaign ad that suggests Romney wouldn't have made the decision to kill Osama Bin Laden. The Romney campaign doesn't much like the president using this as attack ad fodder, and nor, apparently, does Giuliani.

We can't help but remember Giuliani's biggest critics back when he ran for president in 2008. What was it they disliked about him? Oh yes, it was stuff like this, a statement from a 9/11 victims' group:

9/11 Firefighters & Families are deeply offended at how Rudolph Giuliani has exploited the 9/11 terrorist attack to weave a false myth that he is the only person with the credentials and experience to lead the nation as our next president.

With his swat at Obama, Giuliani's starting to sound like his own worst critics. Though Giuliani is focused on negative attacks, he must understand that the President's desire to use his record on issues related to the 9/11 attacks ...