Kerry also accused Bashar al-Assad and his allies of "indiscriminate and savage brutality against civilians," as well as "the unleashing of a sectarian passion."
Professor Roberts called these comments "politically motivated," adding that they are mostly "aimed at domestic audiences."
"I think a lot of the extremity of these statements is to do with a sense of embarrassment because Western policy in Syria has been an absolute disaster. There have been some very poor decisions," he said. Western leaders have "supported groups which have in reality been part of [Daesh or other extremist groups]. It has been an absolute disaster. … They are trying to cover it up. Kerry's rhetoric is trying to cover up Western failure, Western weaknesses and poor political decisions by Western politicians in relation to Syria."
Professor Roberts expressed hope that once the Syrian conflict is resolved, such rhetoric will give way to a "more productive dialogue." He warned that the victory in Aleppo would not put an end to the years-long war since the militants will entrench in rural areas.
"If there is a genuine kind of alliance to bring the war to an end, to find a common solution and to make sure that there is no sectarian bloodletting after the end of the civil war, I think the civil war could come to an end quite quickly. At least to the extent that the armed revolt could be contained and under control in certain areas," he said.
The historian further said that the Kremlin could find common ground with the incoming US administration, adding that there are "certain possibilities."
Nobody knows what Donald Trump will do once he becomes president, "but he does not seem to be anti-Russian," Professor Roberts noted. "He seems to be in favor of détente. He wants to step away from American military interventionism. I think these are all good things. There are some possibilities arising out of that. I am relatively optimistic that the situation could improve in the next few months."
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