Three moments when Gallipoli might have succeeded

The counterfactual changes according to when the breakthrough occurs. A February victory precedes the formal promise of Constantinople to Russia and catches weaker Ottoman defenses; March follows Russian reverses and the territorial promise; April brings troops but also a fully alerted defender. These are treated as separate strategic branches rather than one generic Allied victory. Each delay narrows the Allies' political freedom while increasing the force needed to overcome a defender who now knows where the next attack will fall.