Complicated

Turkey have been fighting the Kurd's since the 80s and but things got a more bit complicated recently as the Kurds were being used by the Americans as their 'feet on the ground' in the battle against ISIS.
In one recent flash point in the Syrian city of Kobani on the border of Turkey, Kurds fleeing an ISIS attack on their city were forced back towards ISIS by the Turkish military.
Turkey are enemies of the Syrian President, Bashar al-Assad, so they did not want to fight ISIS as it will help the Syrian President but now they have joined the fighting with the proviso that as well as targeting ISIS they also attack the Kurds.
Complicated for the US and UK as the Kurds are on our side so we have the farcical situation where Turkey have joined our side but are attacking the people on the same side.
So to recap, the UK, USA, UAE and Saudi Arabia are battling against the people they armed and funded to remove the Syrian President who they are now helping by batting the elements trying to remove him.
Meanwhile, one section of the allies is attacking another while it is being defended by USA planes. 
Got it? Good. Now explain to the rest of us who is fighting who and who we are supposed to be cheering for.