On September 17, Ukrainian forces struck deep into Russian territory, targeting both an oil refinery in Yaroslavl and a military air base in Rostov-on-Don in a single coordinated campaign. The refinery, a pillar of Russia's domestic fuel supply, halted operations under drone attack, while multiple aircraft were reported destroyed or damaged at the southern base. In the long arc of this conflict, such strikes mark a meaningful shift — the boundary between front line and safe rear is dissolving, and the reach of modern warfare continues to expand. What was once considered secure infrastructure n