This will not lead to WW3. The Russians struck what they claim/thought was a terrorist nest in retaliation for the subway suicide bombing. Neither the Russians nor the Syrians will do anything about this because that would be taking ownership of the chemical weapons the Russians told Assad to use.
Result: Trump is now the leader of the free world and those who thought they were still dealing with the cowardly Barry Obama now know they aren’t. North Korea can read the writing on the wall even when it is in English.
We and Russia share an interest is kicking the sh*t out of the terrorists. This means we share an interest in bringing the civil wars in the Middle East to an end. However the civil wars began, we share this interest. There’s room for a deal. A strong president - and only a strong president - can make a deal happen. Donald Trump and Rex Tillerson are businessmen. They are practical and hard-nosed people. I don’t claim to have special insight into this mess, but I think it’s a good thing we have gotten rid of the politicians and brought in the outsiders.