The Great Firewall is just mind-bogglingly big, repressing freedom of speech and information for over 800 million Chinese internet users every year. The Great Firewall is so big that it’s worth asking: how did the Chinese manage to build it in the first place? 20 years ago, our info-sec technology was much less advanced than it is today. China was a second-rate technology power, not even comparable to their position today. Most of all: a firewall, like the one they proposed, had never existed before--or, for that matter, since. How, then, did they pull it off?