 Park Geun-hye was impeached in March 2017 and there was a high probability that Moon Jae-in, who is more friendly to North Korea, would be winning the election.The Trump administration was concerned that the incoming South Korean government would be passive in imposing strong sanctions on North Korea.Tensions on the Korean Peninsula escalated when North Korea conducted its sixth nuclear test on Sept 2017 after firing several ballistic missiles on April 2017.