The prolonged conflict between the United States and North Korea has reached unprecedented levels in recent months, as the leaders of both nations have traded insults and North Korea has continued to demonstrate its nuclear capabilities.

U.S. Secretary of State Rex Tillerson has attempted to calm anxieties, revealing last week that the administration has direct channels of communication set up with North Korean leaders in Pyongyang. He stressed that his primary objective is to find a "peaceful resolution."

However, President Trump upped the ante on Sunday, tweeting that Secretary Tillerson is "wasting his time trying to negotiate with Little Rocket Man," as he often refers to North Korean Leader Kim Jong Un. Casting shade on previous presidents — each of whom Trump says did not adequately address the threat of North Korea's nuclear program — Trump vowed that he "won't fail":