> The state in Taiwan is desperately trying to prevent
> high-tech investment in China, so I don't get your point.
That’s the official story. Dig deeper, and economic/cultural integration has been happening for decades. In AsiaTimes, George Zhibin Gu has this to say:
--------- "In 2004 alone, Taiwan Inc invested $6.94 billion in the mainland. Officially, Taiwan's total investment stood at about $40 billion by 2004. But some people estimate it as high as over $100 billion. This discrepancy in numbers comes from numerous government restrictions on Taiwan investment in the mainland; as a result, many members of Taiwan Inc may go to the mainland from a third location. One popular way is via tax-shelter islands.
Behind the ever-increasing trade, there is an ever-increasing tide of investment from Taiwan Inc. The mainland is its biggest destination already and it now has over 60,000 Taiwan enterprises. It also has more than 1 million Taiwan residents as well. Shanghai alone has more than 300,000 Taiwan residents." (http://www.atimes.com/atimes/China/GE11Ad01.html)
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Similar processes are happening all across East Asia these days, with extensive South Korean investment in China, Singapore in Vietnam, etc.
-- DRR