China has finally given a green light for Disneyland to build a theme park in Shanghai. Negotiations that started when Bill Clinton was in the White House have concluded just before President Barack Obama is due to visit. The approval looks like a coup for Walt Disney Co. (DIS), but it will take all of Mickey’s magic to prevent the park from becoming another government-financed loss maker.

Disney's last theme park in the region was anything but a hit. Hong Kong Disneyland was created in 2005 in an effort to boost employment in the epidemic-stricken region, but attendance numbers have fallen short of target. This hits the Hong Kong government harder than Disney, because the former not only took an initial 57 percent equity stake in the venture, but also spent $1.75 billion building related infrastructure like a metro line and ferry piers.

Shanghai Disneyland is likely to be financed in the same way. Estimates for the park’s price tag are around $4 billion. The government and a group of Chinese companies will contribute about 60 percent of equity, with Disney paying for the rest. The Shanghai government is also likely to pay for the roads leading to the park.

The Hong Kong park has been a disappointment for a number of reasons, some of which might equally be relevant in Shanghai. It is the smallest Disneyland in the world, so it is crowded and not worth visiting for a second day. Culturally, locals identify more with the Ocean Park, which features pandas and sharks and is cheaper. Hong Kong Disneyland’s public image has also taken a hit from a bout of food poisoning and accusations that it has exaggerated visitor numbers.

The Shanghai park will be 3-4 times bigger than the one in Hong Kong, making space for more visitors. But this will also increase the cost of relocating current residents. Some locals are busy adding a second floor to their homes so they can demand more compensation when they move out.

Shanghai has twice Hong Kong’s population, but average income is only about a quarter that of its wealthier neighbor, so it’s far from clear how many visitors will be able to afford a ticket that will cost the equivalent of two days of earnings for a college graduate. Then there is the possibility that the Shanghai park will divert visitors from Hong Kong.

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