Donald Trump's return to the White House is expected to significantly impact U.S. foreign relations, particularly with adversaries such as China, Russia, Iran, and North Korea, with an emphasis on America First policies and military alignment. His second term may see a tougher stance on Iran, including potential sanctions and military actions, as he seeks to counter threats from regional actors. European leaders are apprehensive about Trump's presidency, feeling a shattering of illusions about American politics, while they scramble to maintain relations and adapt to his populist approach. Domestically, Trump has vowed to pursue aggressive investigations against political opponents, indicating a potential for heightened political tensions. His unpredictable nature in foreign affairs will require both allies and enemies to recalibrate their strategies, as global stability hangs in the balance. The ongoing regional conflicts and a new authoritarian axis challenge the U.S.-led order, prompting concerns from close allies about Trump's implications on global security.