Thanks, @finnian.
I don't know enough on the specific topic of ISIS, but I'm aware that America and the UK manufacture many of the world's weapons and that many so-called 'terrorist' groups are often the previous generation of 'freedom fighters', armed and financed by a previous terrorist government in the US or elsewhere.
It's basically a mercenary army to wage war by proxy. Russia knows this and is playing the game wisely. Unfortunately though, most people in the West have no clue, or they ignore the truth as usual.