Verified answer

the great wall of china was built to ward off the huns/ barbarians. in the course of the its past, the great wall of china was only invaded by 2 foreign powers: the mongols & the manchurians.

however, only kublai khan was the only real victor to cross over to china mainland.

the manchurians won over the Ming dynasty was because one of the Ming generals open the gates to let them in.

the silk road has the positive effects on china & its trading partners. all the different cultures exchanged ideas & open up new insights on religion, naval technology, agriculture, etc...

I draw the tip that the chinese language understood why they could desire to "shop their buddies close (the determining to purchase and merchandising companions in the West - the Silk street), and shop their enemies closer (the Mongols to the north - the excellent Wall).