Koki Shigenoi, Visiting Researcher at ROLES, published an essay titled “Signs of a Shift from a ‘Race of Remaining Munitions’ to a Protracted War of Attrition” in Foresight on March 17, 2026.

The essay examines the possibility that the Iran War is shifting from a “race of remaining munitions” between U.S.–Israeli long-range strike capabilities and Iran’s missile and drone capabilities toward a more protracted war of attrition involving maritime traffic, energy infrastructure, and civilian lifelines.

In the previous essay, Shigenoi argued that the United States would likely seek an early exit due to constraints of time, munitions, and domestic politics, while both Israel and Iran had incentives to prolong the conflict. At that stage, the balance between U.S.–Israeli missile defense capacity and Iran’s long-range strike capabilities appeared to be a potential trigger for war termination. This essay revises that assessment in light of developments in mid-March, arguing that the duration of the war can no longer be measured solely by the number of missiles, interceptors, or launch platforms remaining.

A central focus of the essay is Iran’s use of the Strait of Hormuz not simply as a site of blockade, but as an instrument of selective control. Rather than merely “closing” the Strait, Iran appears to be using it politically by determining who may pass and who may be stopped. By combining pressure on the Strait of Hormuz, attacks on regional energy nodes, low-cost drones, and the cost asymmetry between inexpensive offensive systems and expensive missile defenses, Iran is seeking to impose sustained costs on the United States, Israel, the Gulf states, and the global economy with relatively limited resources.

The essay also analyzes why the option of ground operations may become increasingly tempting for Washington. If airstrikes can degrade Iran’s military capabilities but fail to achieve the necessary political objectives, the United States may be drawn toward special operations or limited ground intervention. Yet the essay warns that such an intervention would not necessarily provide an exit from the war. It could instead become the entrance to a longer and more complex war of attrition.

To explain this risk, the essay highlights Iran’s doctrine of “mosaic defense.” This doctrine does not rely on a single centralized command structure, but distributes defense functions across multiple regions, organizations, and units. The Islamic Revolutionary Guard Corps, the regular armed forces, and militia organizations are organized in a layered and decentralized manner, allowing resistance to continue at the regional level even if the central leadership is struck. As a result, decapitation strikes or precision attacks by the United States and Israel would not automatically bring the war to an end.

The essay argues that Iran has adapted its strategy in light of the lessons of the Afghanistan and Iraq wars. Rather than attempting to fight the United States symmetrically, Iran has sought to prepare for a form of warfare in which it absorbs the adversary’s military superiority and transforms the conflict into one that cannot be easily concluded. Limited ground operations or the seizure of coastal facilities may bring tactical gains, but they could also open the way to prolonged asymmetric warfare, local resistance, attacks on supply lines, and attrition in urban and mountainous terrain.

The essay concludes that the central question is no longer simply whose munitions will run out first. The more important issue is how long Iran can externalize the costs of war onto the global economy through threats to the Strait of Hormuz and regional infrastructure, and whether the United States and Israel can neutralize that pressure without being drawn into a ground war. The conflict increasingly displays a logic in which the United States loses if it cannot win, while Iran wins if it does not lose. In this sense, the war may be moving onto terrain where Iran could acquire a relative advantage.

The full essay is available (in Japanese) below:

[How Long Will the Iran War Last? 2] Signs of a Shift from a “Race of Remaining Munitions” to a Protracted War of Attrition
https://que.dailyshincho.jp/node/17134/