MU was on track to join OneWorld. It will be sponsored by CX as CX/MU already in FQTV corporation. Then MU signed a lot of deals with AA/JL/QF and on track with BA in some time.
But the crises within MU and MU start looking for relationship with SQ somehow delayed the process.
Then what happened was the former CEO from CZ come to MU and stopped the process in his personal will and move MU towards SkyTeam.
He judges that JAL stay in OneWorld then DL will have the one billion US dollars to invest in other carriers...Which we all know would be dream on.