Like all repetitive human interaction, even war has been institutionalized and fought according to conventions and norms. Historically, this institutionalization is apparent from the way war has been compared to the duel, first in the 14th century and most famously by Carl von Clausewitz 5 centuries later. This article continues this train of thought and argues that the observed limits of Western “professional orthodoxy” and “strategic vocabulary” can be traced to how war has been institutionalized by the military profession. This offers an alternative explanation to the prevailing views of why the West has struggled in contemporary wars: it is the fundamental mismatch between these professional norms in the West and those held by their opponents that forms the biggest asymmetry in contemporary war. As this asymmetry is unlikely to disappear, these professional norms need to be reconsidered: just like the aristocracy with the duel by the late 19th century, the Western military profession appears stuck in an institution that is increasingly becoming obsolete. Without such reconsideration, the attainment of decision – the central strategic objective in war – and hence victory in future wars will remain uncertain.