Apple’s unpleasant experience in China offers a warning to American tech giants.

The masters of the universe running Apple have just discovered that the Celestial Kingdom is slipping out of their grasp.

China’s recent decision to ban Apple from offering its iTunes Movies and iBooks Store services must have come as a shock to executives at the world’s most valuable company. As Apple’s second-largest market for iPhones, China is critical to the Cupertino-based company’s future. Total revenue from the Greater China region (which includes mainland China, Hong Kong, and Taiwan) now accounts for about a quarter of Apple’s sales. And Apple has invested heavily in cultivating good relations with the Chinese government. CEO Tim Cook has visited China at least seven times since assuming his position in 2011.

Yet the ruling Chinese Communist Party (CCP) does not seem to value such demonstrations of goodwill. The CCP seldom allows sentimentality to get in the way when a foreign company – even an old “friend of China” such as Apple—does something that arouses the party’s paranoia...