Rome, through its history, seems to have been always able to bounce back even if it has experienced numerous periods of disunity, civil wars and even collapses of central government. In contrary to this, China has since the end of Han period stayed almost continually disunited, even though there have been many attempts to unify the whole region, last time during the 20th century. What are reasons for this difference? Could it be reversed?
I know that the enduring Chinese Empire is a sort of cliché here but we have had usually rather interesting discussions about the topic.