But crucially, their arrival probably will not alter the long-term arc of the war – toward a Russian defeat. Even a best-case scenario with these new fighters does not point toward a Russian strategic victory and the end of conflict, but rather toward a longer, harder slog – which Ukraine will still win, albeit after much more bloodshed.
Assume for a moment a highly positive (but very unlikely) outcome for the new Russian troops: They stop the Ukrainian advance, start conquering new swathes of territory and even march on in Kyiv again.
Even if the Russians got this lucky, it does not end the war. There is nothing in opinion polls of the Ukrainian public or in its elite discourse that suggests Ukraine will surrender, even if badly defeated.
If Russia somehow managed to conquer most of the country, the Ukrainians would probably launch an insurgency. In fact, many analysts expected this back in February and March when Russia looked militarily superior.
Just as the Ukrainians have put up a tough resistance for months, an insurgent effort will likely dog the Russian occupier for years, much as the Afghans did against the Soviet Red Army in the 1980s. Eventually, the Soviets tired of that war and went home; the outcome would likely be the same in Ukraine.