Nasdaq closes it's China board because the Government launched it's own competitor, which was naturally more successful. Very interesting. Will techno-nationalism shrink the pie for everybody? Yup. Will China still launch techno-nationalist offensives in every business it can? Yup.
Why? Because it's better to have a bigger piece of a small pie than a small piece of a big pie - this is anathema to all the nice things you learned in business school. But it's true: because it's a simple matter of leverage - you've got more in the former situation than the latter. And that's the goal of any kind of nationalism, or even corporatism: leverage over other people's outcomes, not maximizing wealth.