One of the enduring dilemmas in understanding and planning Ukraine’s defence is that there is no simple or decisive solution in sight. Classical strategic thought, dating back to German historian Hans Delbrück’s⁽¹⁾ early twentieth-century work, distinguishes between two pathways to victory: annihilation or exhaustion. Either the enemy is destroyed in a decisive battle, or it is worn down by attrition until its will collapses. In the case of Russia’s war against Ukraine, neither path offers a realistic or sustainable prospect.

Annihilation of Russia’s armed forces is beyond reach. Even if Ukraine and its allies were to mobilise greater resources than today, the prospect of completely dismantling the extremely well resourced Russian military machine is improbable. Western capitals, particularly Washington under the Biden administration, have repeatedly signalled that escalation must be contained. Assistance has been substantial but carefully calibrated, avoiding the provision of certain systems for fear of widening the conflict or provoking a nuclear response. This policy has succeeded in preventing a NATO–Russia confrontation, but it has not brought resolution.

Exhaustion, on the other hand, appears equally unpromising. Russia has absorbed extraordinary losses in manpower and materiel—well over a million casualties, the destruction of thousands of vehicles, and severe strain on its economy⁽²⁾—yet it has not conceded. Unlike smaller powers, Russia can sustain a protracted war, particularly with Chinese backing. Putin has also recast the war as existential, embedding it into the very legitimacy of his regime. In this context, endurance itself becomes a form of strength, and attrition becomes a trap: the longer the war drags on, the more it risks draining Western unity rather than Russian resolve.