Suppose The Great Wall of China is a series of fortifications made of stone, brick, tamped earth, wood, and other materials, built along an east-to-west line across the historical northern borders of China to protect the Chinese states and empires against the invasions and raids of various nomadic groups. Several walls were being built as early as the 7th century BC; these, later joined together and made bigger by Qin Shi Huang, the first Emperor of China.
Can we infer that "The Great Wall of China was built to protect against invasions."? Yes, no, or maybe?