It was nice of Russia to help create the problem by going all-in to support the dictatorship. Iran has trained 50,000 paramilitary thugs, and they’re not going to accept any “negotiated” settlement. Assad will have to be assassinated to leave office. He started the bloodshed (if one doesn’t count the massacres carried out by his father), and now every jihadist faction on Earth appears to be fighting inside Syria, or recruiting proxies (as Iran has done, training Syrian thugs and employing the Hizzies from jihadist occupied Lebanon), all fighting each other. The main combat phase may go on for two or three more years, but there will be no more unified faux-nation of Syria.
Good.....Let 'em all kill each other and let Allah sort it out.