ABSTRACT
This chapter examines the reaction of the U.S.A. and its European partners during the “Ukraine Crises,” encompassing at least three different crises relating to a distinct threat to Ukraine’s legitimacy, sovereignty, and territory. The chapter thus deals with a crisis vis-à-vis third parties (namely Russia). Although the emergence of a powerful common adversary encouraged further transatlantic coordination, the outcome of transatlantic actions exposes the limited effectiveness of transatlantic cooperation when addressing challenges posed by other major powers. Interestingly, the Trump presidency has so far produced a continuation instead of a rupture of this pattern, as the empirical part of this chapter highlights.
