If the YPG is given the land East of the Euphrates, what becomes of the Assyrian Christians along the Khabour?
Yes, the two have battled ISIS together, but prior to that the YPG was no friend of the Assyrian Christians.
How far back do you refer? The YPG are a pretty recent organization. Was it in Iraq or Syria? Note, Kurds in Syria are very different from those in Iraq. Iraq Kurds are 98% Muslim, Syrian Kurds vary a great deal depending upon community. Some Kurdish communities in Syria have a large Christian component. Only recently I discovered that in Efrin, there is a Alevi component of Kurds, they once sheltered Christians in Iraq. For that they were treated like the Armenians by the Turks.
There are no sure things in the Middle East. I'm impressed by the honest practical side of the YPG/YPJ in Syria. I'm close to some of them. But their attitude toward Ocalan is puzzling.
I was told long ago that Syrian Kurds were very cautious to discuss how many Christians and other persecuted groups were in Syria. I found a map of Iraq once, that showed the religious makeup of the communities in Iraq. Have never seen anything like that for Syria. I'll see if I can find that map.