Those battlefield victories set the tone for subsequent U.N.-brokered talks in Geneva, as well as the conditions of a tentative cease-fire in Syria that were agreed upon last month by the United States and Russia. It led to admissions from senior U.S. officials that the Russians had “changed the calculus” of the conflict.

“One can doubt that Russia reached all of its goals, but it is difficult to dispute that the Russian operation provided the circumstances for the current ceasefire,” writes Nikolay Pakhomov, a political analyst at the Russian International Affairs Council, which is based in New York City. “The clarity of Moscow’s moves, whether one can agree with them or not, has accelerated Russian interactions, if not cooperation, with the countries in the Middle East. Major regional actors are aware of Russian motives, interests, capabilities and goals and they can act accordingly.”

That clarity, as Pakhomov put it, stands in contrast to the perceived waffling of the Obama administration, which had long called for Assad’s departure but didn’t follow through with decisive action, particularly when it deemed the regime’s use of chemical weapons a “red line.” In Iraq and Syria, the United States launched a concerted military campaign against the Islamic State, but has tried its best not to get too deeply entangled in the Syrian war on behalf of Assad’s opposition.