Maybe it was.
All the takeover of the South China Sea, war with India, war with Russia, war with Vietnam on its borders, the destruction and colonization of Tibet, yeah... all just inward looking...
As I said they get into little scraps. But, the ones you mentioned generally did not last long and there has no full scale war that they have been in since Korea. Most of the violence occurred during Mao’s regime and that is when they were the most aggressive. But even Mao seemed to moderate in his later years and they have been back to the norm. I see no evidence in the current China that they want to invade great swaths of Asia or mix it up with us.