Jeffrey Wasserstrom is Chancellor's Professor of History at the University of California, Irvine. His most recent book is China in the 21st Century: What Everyone Needs to Know.

IRVINE, CALIFORNIA – We live in an era fascinated with David-versus-Goliath tales. The Biblical confrontation is invoked to describe everything from sporting contests to popular uprisings against dictators. Malcolm Gladwell’s forthcoming book David and Goliath: Underdogs, Misfits, and the Art of Battling Giants promises to give the story the ultimate pop-culture treatment. And the parallel between the classic tale and the unfolding story of the former intelligence contractor Edward Snowden’s solitary battle against America’s massive security establishment is inescapable.

But Snowden received help from an unexpected source, Hong Kong’s government, which disregarded a US request to hold him to face espionage charges and allowed him to leave for Moscow. In fact, Hong Kong’s siding with a “David” should not surprise us, given that its relationship with mainland China is the quintessential David-versus-Goliath story – and it is still in progress.

Mainland China was not always Goliath; the modern People’s Republic was once David. Indeed, every year on October 1, the country celebrates National Day, commemorating the unlikely victory of the Chinese Communist Party (CCP) in 1949 over Chiang Kai-shek’s Nationalists, who had nearly exterminated them in the 1930’s....