This is probably the economic equivalent of banning say mobile phones or some other large and important sector.
For years the thinking has been that China is liberalizing, and it will eventually open up and that reciprocal sanctions or tariffs will spark unnecessary protectionism and encourage China to reverse direction.
A lot of people now, after 20-30 years of similar behaviour, believe that China was just gaming the system all along and had no plans to liberalize politically or allow fair competition from foreign business. Trump certainly tapped into that (although I think there's some consensus that punitive tariffs still won't be useful).
In the case of an import tariff, it is paid entirely by consumers, and domestic suppliers get a windfall from it, rather than sharing the burden. That's because there are two supply curves in play, domestic and international, and only one demand curve, because consumers generally don't care where the goods come from, and the internal trade of foreign markets is ignored.
2. No single country has a monopoly on innovation. Consequently the sharing of ideas from different locations and cultures is really important for moving forward. You miss out on this benefit when you consciously work to block it. Historically, the last time China was this arrogant about isolation, it didn't turn out too well.
Last Update: I've wasted enough time on this and probably should have put this in my original post.
If you think of sharing data as a resource, China just made it artificially scarce, made it extremely slow, and made it really costly which makes total business sense in the Information Age /s Hopefully our governments won't follow
They are isolating data, but hoarding data is a competitive advantage in a way that isolating knowledge isn't.
Ok they are bottlenecking data... As I've already mentioned this is an extremely inefficient way to share data. Sharing data using physically present word of mouth is a lot more expensive and slower than sharing it instantly via an open internet connection.
"Sharing data using physically present word of mouth is a lot more expensive and slower than sharing it instantly via an open internet connection."
Foreigners can set up businesses - see for example, the WFOE [0].
There are restrictions however for certain fields and business activities (infrastructure being one), so while foreigners can't just set up any company, they certainly can set up some companies if they like.
0: https://en.wikipedia.org/wiki/Wholly_Foreign-Owned_Enterpris...
2. You seem to assume the bulk of innovation is going to be happening outside China and that blocking consumer access to Western platforms would somehow inhibit a flow of information to China. I'd disagree on both counts. The Chinese government is acting as the word's biggest VC and is also very practised and willing to take on long-term transformation plans at the national level. Shutting down foreign platforms only drives adoption of home-grown ones. In addition, they are explicitly targeting a future position as the world leader in AI. In the West I'd be betting on the MIC over individual privately owned companies to put any kind of dent in that ambition. I think any moment where Apple or Google alone could outspend and outcompete China in tech is gone.