How long a Nuclear war goes?

Former UN Weapons Inspector Scott Ritter was discussing about the potential duration and implications of a nuclear war in a recent discussion event. He emphasized the catastrophic consequences such a conflict would have on the world and urges for global awareness and prevention measures and I felt that I should share at least a minute of quote from his speech here with my friends. Below is a short less than one minute message from Mr.Ritter one should listen to: