One of the fastest growing—and underreported—subjects in international relations is the rise of private armies. Dr. Sean McFate, Atlantic Council senior fellow and former private military contractor, joins Doorstep co-hosts Nick Gvosdev and Tatiana Serafin to discuss his book The New Rules of War and how our current paradigm of warfare is obsolete. With cyberweapons, disinformation, and mercenaries presenting new threats, how can America shore up its defenses and rethink the trillions of dollars spent on defense? Is the risk of inaction creating a new "Middle Ages"? For more on this subject, don't miss Carnegie Council's panel on December 14 at 3pm ET,  "Is Militarization Essential for Security in 2022 and Beyond?" And, for more on this podcast, please go to carnegiecouncil.org.