The war with Ukraine entered a new phase this month with Kyiv’s incursion into Russia’s Kursk oblast. The government of Russian President Vladimir Putin was surprised by the bold move and morale among Ukrainian forces has improved. It is not clear what the ultimate goal of Ukraine’s surprise attack is, however, and whether it foreshadows grander ambitions.

Ukrainian forces are overextended and Russia has not been forced to relinquish gains acquired elsewhere in the conflict. Putin is no doubt embarrassed by these developments, but that has happened before. It is unlikely to force him to rethink his war aims. Kyiv, though, has acquired additional leverage to negotiate a cease-fire or exchange prisoners. The advance has not, however, fundamentally transformed thinking in either capital. This conflict will continue.

On Aug. 6, Ukraine launched the largest incursion into Russia since the war began in February 2022 — or since World War II, for that matter. An estimated 10,000 troops, supported by Western equipment including armored fighting vehicles, poured into the Kursk oblast, about 500 kilometers south of Moscow, seizing up to 1,000km of Russian territory within a week and forcing an estimated 200,000 Russian civilians to flee their homes. (All numbers are estimates; statistics at this time are unreliable.)