China turned out the lights on Facebook (FB) in 2009, and there are no signs that Beijing plans to restore access to the U.S.- based social media platform.

Some analysts trace the ban to riots that broke out in July of that year between Muslim Uighurs and Han Chinese in the restive western region of Xinjiang.

But others also cite a protectionist commercial motive.

China-based social media sites are allowed to operate in the country, which helps to promote the domestic tech industry. Still, these platforms are heavily censored. Domestic operators accept this as a fact of life, while western tech firms are much less likely to give up control.

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