Nationalism significantly impacts international relations by fostering a sense of identity and unity among groups within a nation. This can lead to increased tensions between nations, especially when issues of territorial integrity or self-determination arise. Nationalistic sentiments may drive countries to adopt more aggressive policies, potentially resulting in conflicts or trade disputes. Conversely, nationalism can also encourage diplomatic engagement when nations prioritize mutual interests or seek collaboration in facing global challenges. Overall, nationalism can be a double-edged sword, influencing cooperation and conflict in the international arena.