The Department of Homeland Security is requesting 20,000 National Guard members for help with the Trump administration's crackdown on immigration at the southern border. New York Times Pentagon Correspondent Helene Cooper and Senior Editor at The Atlantic Hanna Rosin join Katy Tur to explain more. For more context and news coverage of the most important stories of our day click here: https://www.msnbc.com/ » Subscribe to MSNBC: https://www.youtube.com/msnbc » Subscribe to MSNBC on TikTok https:/