You can critically support left wing nationalism. The Algerian liberation movement was a nationalist effort that resulted in Algeria no longer being a colony of France. Of course, Algeria is not a communist utopia, they are still ruled by their bourgeoise, but the lives of average Algerians are indubitably better now than when it was a colony, just as lives of poor Native Americans would be better if they also were not ruled by the settler colonialists who are still doing genocide to them.