Walter Isaacson, author of ‘Elon Musk,’ joins ‘America’s Newsroom’ to discuss Musk’s departure from the Department of Government Efficiency and what’s next for the billionaire entrepreneur. Subscribe to Fox News! https://bit.ly/2vBUvAS  Watch more Fox News Video: http://video.foxnews.com  Watch Fox News Channel Live: http://www.foxnewsgo.com/FOX News Channel (FNC) is a 24-hour all-encompassing news service delivering breaking news as well as political and business news. The number one network