Now that Barack Obama is visiting Iraq, his opponent John McCain has challenged him to recant his disapproval of the troop surge.  

The fact that the challenge comes only now bears the silent premise that Sen. Obama could not have known if the troop surge worked without visiting Iraq. “He'll be able to have the opportunity to see the success of the surge,” McCain told Good Morning America as if before, Obama was unable to have that opportunity.

As long as challenges are being meted out, I have one of my own to propose...Apparently, the McCain campaign is governed by the premise, “You have to see it to believe it.” From that it follows that we regular people, since we have not visited the country (too dangerous for civilians to visit), could not possibly understand how safe it is.

As long as challenges are being meted out, I have one of my own to propose: Sen. McCain, I challenge you to stop making the same flawed argument over and over.  

When Republicans, military men, and all-around fuddy-duddies assert that lower levels of violence and fewer combat deaths in Iraq imply that the surge is working, they are willfully misremembering the war’s purpose. The mission in Iraq is NOT to lower combat deaths or even to have U.S. troops diminish violence in the region. The mission is to train Iraqi soldiers to be capable of diminishing violence in the region on their own, a mission which is undermined when we simply do it for them.

...Senator McCain: I challenge you to stop making the same flawed argument over and over.Of course, still others have been arguing that the Surge has nothing to do with diminished violence in the region. Some tactics (like paying off Baathists to fight Al-Qaeda forces so U.S. troops do not have to) are not sustainable, and others (like the touted “Clear, hold, build” strategy) fail as soon as Iraqi citizens take over. So even if Obama did witness a placid and safe Iraq, he would have no reason to conclude from that fact that the surge works.

McCain, who used to be known for his "straight-talk express," now propels his campaign by sophistry.

Either McCain is too willfully ignorant to see his mistake, or worse, he proceeds anyway.
[ABC News, Fox News, CNN on YouTube, Huffington Post]