What he is trying to say is there is no such entity known as India. A Chinese guy like me can read a text almost 1500 years ago easily. The script and meaning didn't change much.
You need to understand the largest most disruptive nomadic invasion force was living just next to China. Mongolia. We still stayed intact after a Mongol invasion, a Manchu invasion and yes even the Arabs were near our borders in Xinjiang. The ancestors of the Turks were living in Xinjiang and constantly attacked us. China stayed unified despite all of these threats, unlike the Indians, we built a wall.
It did help for the first few centuries, the Hun/Proto Mongolians were forced to migrate to the steppes and eventually threatening Europe because of it. Later stages, Northern tribes couldn't penetrate it until 1644 when a Han General opened the gate because the Ming Emperor had already died in Beijing due to rebellion.
i assume with gunpowder the wall was symbolic
Gunpowder warfare was only predominant in the 1500/1600s, before that the wall was an important defense structure defending Han China from barbarians, the fall of the Roman empire could be attributed to steppe nomads migrating to Europe instead of China due to the wall. The Huns kept on moving westward and finally gave up attacking China until the Mongol period in the 1200s, even then the Mongols came from the West side instead of directly attacking China.
