In my company we are split in 3, US, EU, APAC, and we have the same issue with global outage for stuff we could have just managed regionally. For all the savings of the global architecture, they disappear each minute a client is down on a global outage because a guy thousands of kms away messed up.
You dont have to unify, at all. You dont unify with your competitors, and the world has not exploded: compete internally between regions ?