Sensing a moment of political vulnerability on national security, Republicans pounced Friday on disclosures that President Obama's administration could have known early on that militants, not angry protesters, launched the deadly attack on U.S. diplomats in Libya. Within 24 hours of the Sept. 11 attack, the CIA station chief in Libya reported to Washington that there were eyewitness reports that it was carried out by militants, officials said. But for days, the Obama administration blamed it on an out-of-control demonstration over a video made in America ridiculing Islam's prophet Muhammad. Paul Ryan, the Republican vice presidential nominee, led Friday's charge....