Knowing what he knows now about the reaction to his statement that knowing what he knows now he would still have gone into Iraq, Jeb Bush on Friday comically reversed course on his brother's 2003 invasion of Iraq. Even more side-splitting have been the responses of Jeb's rivals for the 2016 Republican presidential nomination. Casually discarding over a decade of GOP talking points, Florida Senator Marco Rubio declared that knowing what we know now:

"Not only would I not have been in favor of it, President Bush would not have been in favor of it."

As it turns out, Rubio's claim is doubly pathetic. After all, Mr. New American Century repeatedly defended topping Saddam Hussein, including as recently as six weeks ago. More ridiculous still was Rubio's failure to check with President Bush himself: the "Decider" has never had second thoughts about the world-historical disaster he launched in Iraq.
Writing in the New York Times, Peter Baker helped catalog Dubya's defense of the indefensible. For example, in his 2010 memoir Decision Points, Bush explained:

"Imagine what the world would look like today with Saddam Hussein still ruling Iraq," Mr. Bush wrote. "He would still be threatening his neighbors, sponsoring terror and piling bodies into mass graves."
"Instead," he added, "as a result of our actions in Iraq, one of America's most committed and dangerous enemies stopped threatening us forever."

As President, Bush didn't just reject the idea that the decision to oust Saddam was a mistake; he struggled to name a single mistake he made during his tenure in the White House. In an April 2004 press conference, Bush hilariously replied, "I'm sure something will pop into my head here" when asked about errors he had made in office. In 2007, he answered the same question from Scott Pelley of CBS 60 Minutes this way:

"You know, we've been through this before. Abu Ghraib was a mistake. Using bad language like, you know, 'bring them on' was a mistake. I think history is gonna look back and see a lot of ways we could have done things better. No question about it."

WMD or no, Bush continued to show no qualms about his Iraq cataclysm. In London in June 2008 as part of his final swing through Europe before leaving the White House, President Bush told The Times of London that his cowboy rhetoric was perhaps his greatest regret:

President Bush has admitted to The Times that his gun-slinging rhetoric made the world believe that he was a "guy really anxious for war" in Iraq.
[...] In an exclusive interview, he expressed regret at the bitter divisions over the war and said that he was troubled about how his country had been misunderstood. "I think that in retrospect I could have used a different tone, a different rhetoric."
Phrases such as "bring them on" or "dead or alive", he said, "indicated to people that I was, you know, not a man of peace."

Just this past November, the former president used the press tour for his biography of his father to once again defend the rightness of his March 2003 invasion of Iraq. If "bad language" had been his only regret while in office, by the end of 2014 Bush's lone misgiving was the rise of ISIS:

"I think it was the right decision. My regret is that a violent group of people has risen up again. This is al Qaeda plus. I put in the book that they need to be defeated. And I hope they are. I hope the strategy works."

(Of course, we all do. But Dubya should more than anyone else. After all, as Republicans might put it: ISIS? Bush built that.)
As the Times' Baker notes, Vice President Dick Cheney and Defense Secretary Donald Rumsfeld have always stood by the decision to invade and occupy Iraq, WMD or no. But like most the 2016 GOP field, even some of Bush's closest advisers have tried to have it both ways. In his own memoir Courage and Consequence, Karl Rove blamed himself for not lying more about the war. As Baker wrote at the time ("Rove on Iraq: Without W.M.D. Threat, Bush Wouldn't Have Gone to War"):

"Would the Iraq War have occurred without W.M.D.? I doubt it," he writes. "Congress was very unlikely to have supported the use-of-force resolution without the W.M.D. threat. The Bush administration itself would probably have sought other ways to constrain Saddam, bring about regime change, and deal with Iraq's horrendous human rights violations."
He adds: "So, then, did Bush lie us into war? Absolutely not." But Mr. Rove said the White House had only a "weak response" to the harmful allegation, which became "a poison-tipped dagger aimed at the heart of the Bush presidency."

President Bush's former press secretary Ari Fleischer lamented Jeb's performance on Iraq this week. "No, it was not handled well by Gov. Bush," Fleischer admitted, "I don't know why he said what he did." This is how Fleischer himself recently addressed the "knowing what we know now" question on Iraq:

"I just don't think he would have gone to war. I think he would have turned up the heat on Saddam, but I don't think he would have gone to war."

Of course, that's not what Ari Fleischer was saying before. As he put it to Chris Matthews in March 2009:

"After September 11th having been hit once how could we take a chance that Saddam might strike again? And that's the threat that has been removed and I think we are all safer with that threat removed." [Emphasis mine]

Only time will tell whether Jeb Bush, Marco Rubio or any of the other Republican White House wannabes say anything so ridiculous or regrettable about Iraq. As for George W. Bush, he has no real regrets at all.