The video lasts just more than three minutes. But that’s long enough to raise some nasty doubts about John McCain’s reputation as a straight talker.There’s the Arizona senator arguing both sides of President Bush’s tax cuts. Here’s the supposed foreign policy wizard flubbing the simple facts about which terrorists are being trained in Iran. He’s even ducking his own admission that he needs to learn more about economics.The newsreel of McCain lowlights has zoomed up the YouTube charts in the last week, with more than 1.5 million views. “John McCain’s YouTube Problem Just Became a Nightmare” is the video’s title, which might be dismissed as partisan hype, but for one thing: It’s true.The presumed Republican presidential nominee is taking a serious drubbing on YouTube.There’s McCain stumbling over a debate question, and worse, his cringe-worthy answer wickedly paired with the hapless Miss Teen USA contestant who went blank on a query about Americans and geography.There’s McCain, seemingly on the verge of swallowing his tongue, so great is his discomfort when Ellen DeGeneres demands to know why women like her shouldn’t be allowed to marry other women.