Except that AA has JVA with BA/IB and the US/AA merger terms seem crafted to keep that Joint Venture in place without affecting terms. EK is more likely to partner with Jetblue than AA Oh wait, they already do

Can a founding member leave Oneworld? Are there special terms that apply, such as automatically dissolving the alliance? I suppose it can be immediately reconstituted, but then it would be called TwoWorld.