European leaders are concerned about Donald Trump's threats to seize Greenland, with bipartisan opposition growing in the US Congress. Republican leaders, including Don Bacon and John Thune, have publicly condemned the idea, emphasizing the importance of NATO alliances and the negative implications of such actions. The Republican party is divided over Trump's military approach, with many viewing the Greenland issue as a distraction from more pressing domestic concerns. As midterm elections approach, Republicans are wary of supporting Trump's Greenland ambitions, which polls show are unpopular among Americans.