This stick references a pivotal moment in the Three Kingdoms period (220-280 CE), one of China's most turbulent eras. Lu Su was a brilliant diplomat serving the Kingdom of Wu under Sun Quan. The story centers on Jingzhou, a strategic territory that Liu Bei had 'borrowed' from Wu during desperate times, promising to return it later.
When Wu finally sent Lu Su to diplomatically reclaim Jingzhou, Liu Bei found himself in an impossible position. He had grown attached to the land and its people, but knew he lacked the military strength to resist Wu's legitimate claim. The tears mentioned in the poem represent Liu Bei's anguish at having to give up something precious, not out of defiance, but out of painful acceptance of reality.
This became a classic example in Chinese culture of how sometimes we must surrender what we've grown to love when we cannot rightfully keep it.