The exclusion of some rebel groups from peace negotiations can perpetuate civil war, rather than hastening a resolution.
Negotiations
Defense Secretary Jim Mattis indicated this week that the U.S. will lift a suspension of joint military exercises with South Korea. This announcement, in addition to President Trump's recent cancelation of his State Department's visit to Pyongyang, goes against what Peace Science tells us about the importance of granting concessions and avoiding provocations during intense negotiations.
North Korea says joint U.S./South Korean military exercises are jeopardizing the upcoming summit between Trump and Kim.