Former U.S. ambassador John Bolton criticizes President Trump's escalating rhetoric on acquiring Greenland, possibly by military force, because of security concerns. "This is a tragedy that just unfolds day by day, causing us more and more harm," Bolton tells "NewsNation Prime." Trump's Greenland threats aren't real, but they're harmful: John Bolton | 5:24 NewsNation | 2.52M subscribers | 302,702 views | January 18, 2026