The United States and Russia hold over 90 percent of the world’s nuclear weapons. A strategic nuclear missile launched from the United States can hit Russia in about 30 minutes. Russian missiles can go just as far, just as fast.  Efforts between the two countries to negotiate limits on these kinds of weapons go back to the end of the Cold War. The latest agreement between Russia and the US needs to get past the US Senate. And that is not a sure thing by any means. Todd Grosshans gives us this report.