The obvious answer is political censorship, but there also exists a persuasive economic argument. By blocking, or inhibiting the performance, of foreign Interne

The obvious answer is political censorship, but there also exists a persuasive economic argument. By blocking, or inhibiting the performance, of foreign Internet products, China gives a "head start" domestic clones (e.g. Baidu<->Google, TenCent<->FB, etc) to corner the market. The GFW effectively hamstrings foreign products, making it easier for domestic companies to compete in their early growth stages.