Good God! They're actually practicing doing this....US Army soldiers clear a mock North Korean Underground Facility (UGF) during a Counter-WMD training exercise called Operation Centurion Blitz in South Korea

Just plain wow. Heard of "DARPA Hard"? It once meant that a problem was so hard that only DARPA could get their arms around it. I guess this is the "SOCOM Hard" version of things. I just don't know. I consider it a suicide mission and I can't see how they have any conducted any wargames where the casualty rate wasn't over 90%. They've got to have a trick in their bag to even consider this shit. Maybe some type of super quick incapacitating gas that leaves the target either severely injured or dead within microseconds of inhalation? Has to be something cause if they're just doing it conventionally then its a non-starter from jump.