BALKANIZE is validvalid

to divide into mutually hostile [v BALKANIZED, BALKANIZES, BALKANIZING] : BALKANIZATION [n]

90,928 of 196,601 in NWL2023·also valid in CSW24

to divide (a region or territory) into small, often hostile units, also BALKANISE [v BALKANIZED, BALKANIZING, BALKANIZES]