The recent territorial loses by the ISIS confirm this argument. When the Americans were "bombing" the ISIS, the latter added on territory and expanded across Syria and Iraq. But once the Russian airstrikes started, the ISIS territory started shrinking, and now they are on the run. The ISIS has been kicked out of strategically important cities such as Palmyra and Al-Qaryatayn. They are about to lose Raqqa as well.
exactly my friend , ISIS used to have the most power when the US and its allies were attacking them
but I said it before as a Syrian , US were not mainly targeting ISIS indeed they were targeting our resources that was under ISIS control
so their goal was to destroy the resources that the Syrian people own in order not to benefit from it in the future
their goal was to destroy these resources without killing many of ISIS fighters