Nationalism affects foreign relations by emphasizing a country’s sovereignty and interests over international cooperation. Strong nationalist sentiments can lead to prioritizing domestic policies, sometimes at the expense of diplomatic relations with other nations. For instance, nationalist governments may adopt protectionist measures, complicating trade dynamics and straining alliances. This can result in a more confrontational stance on issues like immigration, defense, or climate policies, which may alienate or provoke other countries. Ultimately, while nationalism can unify citizens at home, it can also create tension and challenges in the global arena.