Soon after President Donald Trump forcibly removed Venezuela’s Nicolás Maduro from power, he laid out what he called the “Donroe Doctrine,” a framework for U.S. dominance over its neighborhood. It was, in classic Trump fashion, both a throwback and something novel: Former President James Monroe had first articulated his eponymous policy vision in 1823, when he opposed European interference in the Western Hemisphere. Now, Trump had revived it—with a new label.