and american and australian kobe is crap. its not kobe, they just bought a couple wagyu breed (thats what kobe beef is, kobe is just an area in japan) and started to brred and kill them.
wagyu is a specifically breed pedigree cow that already is highly prone to marbling in its meat. its about how the cow was raised, what it was fed etc etc that determines the true quality of the meat.
to give you perspective, angus beef has an average bms of 2, AAA prime has an average of 3. most high end australian and american kobe is 6-7. you have to be at least 6 to be considered kobe beef.