I do not think that the destruction of several old Syrian aircrafts will somehow affect the war of Russia against terrorists in Syria.
The US are raising stakes... And we are waiting for response from Russia. It will not be a nuclear attack against the US - there are no crazy idiots in Russian leadership, who want to destroy civilization. I hope there no such idiots in US, too.
Let's wait. Perhaps Putin will not do anything at all - he will simply continue to destroy the terrorists, as if nothing happened.