Russia’s ill-advised invasion of Ukraine and the United States’ equally stupid war with Iran suggest that we have entered a new world of “defense dominance,” a world where larger and more powerful states find it hard to conquer territory or to get much weaker states to make big concessions. United Nations Secretary-General António Guterres apparently thinks so, telling the Financial Times, “If you look at what happened in recent times, the capacity of superpowers to impose their will or their strength or their force in several situations has been severely limited.”
The proximate causes aren’t hard to identify—the development of sophisticated drones and accurate missiles, as well as improved surveillance and targeting capabilities that have made it harder for large units to operate in the open where they can be targeted by hidden defenders. Similarly, expensive power projection capabilities (aircraft carriers, stealthy aircraft, and the like) are becoming vulnerable to defenders and are having a lot of trouble trying to eliminate cheaper and easy-to-conceal drones and ballistic missiles. In the hands of a resolute enemy, these novel capabilities have made it easier for even comparatively weak adversaries to mount a potent defense of their home territory and even impose costs at a distance, which in turn makes it harder for objectively stronger powers to compel them to surrender.
