But then Russia got a different leader who decided that all of Ukraine is really Russia. How do we prevent another Russian leader coming down the like in 20 years and rejecting whatever deal is negotiated now?
I think that for any deal to truly lead to permanent peace, it has to be backed by security guarantees, end eventually NATO membership.
My proposal was to break off Western Ukraine, the part that traditionally belonged to Austria Hungary, and allow them to join NATO, while declaring the rest of Ukraine as neutral, not unlike the agreement that is still in place with regards to Austria.