Gleaming futuristic megacities, China has many of them.

I don't even recognize how impressive or extraordinary they are in the city as opposed to someone who comes here for the first time.

They grew at a mind-boggling pace with help from central planning.

I'm Carolyn Beeler.

And I'm Marco Wurman.

Today we're talking about China as a global superpower from tech innovations to military might.

The next 12 months, though, might reveal fragility.

It's going to be very difficult for the world economy to have a good year ahead if China doesn't correct its own growth model.

There's also tension with that island off of China's coast.

China believes that Taiwan is part of China and wants the rest of the world to agree with them.

Taiwan has heavy metal music on its side though.

We're looking at China today on the world.

This is the world. I'm Marco Werman.

And I'm Carolyn Beeler. Thanks for being with us today.

If I say superpower, I am betting two countries come to mind, the United States and the People's Republic of China.

50 years ago, the idea that China would be a major global rival to the U.S. was tough to

imagine. The country was overwhelmingly poor in the 1970s. Most of the population lived in rural areas.

Today, China is a high-tech powerhouse.

We start our special one-hour broadcast all about China in the southern megacity of Shenzhen, population 20 million.

The world's Jeremy Siegel explains how Shenzhen sidestepped problems typical of cities that undergo rapid growth, like air pollution and overcrowding, to become a global hub of commerce and tech.

It is a hot day in Shenzhen, nearly 100 degrees, even though it's almost winter. During summers here,

the heat can be unbearable. But that's not much of a problem for Wen Xin, a 20-something who was born and

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