The YPG have been making huge strides in just the last two years but especially the recent push towards Raqqa. The war in Syria is a complex and constantly changing conflict; no one seems to really have an idea of when it will be over and who will be the top dogs when the dust settles. Foreign volunteers may find themselves in a sticky situation as the war progresses and the Islamic State in its conventional form dies out.
The following footage is of some foreign volunteers fighting on the outskirts of the city of Manbij. The three fighters can be seen setting up against a wall and firing an RPG (Rocket Propelled Grenade) at a building held by Islamic State fighters. A staccato of gun fire can be heard erupting all around them as they move into position nonchalantly, the YPG fighters are clearly seasoned in this kind of warfare.