Is the Ukraine crisis a new version of the classic tension between political idealism and political realism? By returning to the principles of realpolitik espoused by Professor Hans J. Morgenthau, this piece explores the pitfalls and challenges confronting the United States and its allies in Ukraine. In short, to champion realism in contrast to idealism is simple in principle, but difficult in the practice of diplomacy and international affairs. The practice of diplomacy, like that of politics, is both science and, ultimately, an art. With that in mind, the assertion of strong political will by the American president, leaders of the major member states of the European Union, and the president of the European Commission will be indispensable requirements in mediating any further crisis.