Responding to concerns that lawmakers in Washington will fail to reach an agreement on raising the country's debt threshold, credit ratings agency Moody's placed the U.S.'s credit rating under review for the first time since the federal government shutdown in 1995. The U.S. still risks losing the Aaa rating it has had since 1917, even if lawmakers come to a last minute agreement before the August 2 deadline. In bipartisan meetings at the White House last night, President Obama reportedly walked out of the meeting in frustration with Congressional Republican leaders, whose rank and file members continue to insist any deal not include tax increases. Worried that voters will ultimately hold Republicans accountable if the government defaults, Senate Republican leader Mitch McConnell is advocating a procedural plan that will allow President Obama to raise the debt limit without Congressional approval. Takeaway Washington correspondent  Todd Zwillich  and New York Times Wall Street and financial reporter Louise Story  have been following the debt talks, and talk about the political and economic impact of the latest developments.