[coldtea]

Several factors.

(1) Econ 101 classes mostly sell students an idealized version of economy.

(2) Top-tier countries have used all kinds of techniques (protectionism, tariffs, etc) to get successful, but now that they don't need those anymore, they pay lip service to the Econ 101 "laws" that are against those same techniques.

(3) While clothed in scientific parlance, a lot of what is Econ 101 is just BS to promote the interests of those in power, not what's best for the people in general (that's how an ecomomics professor gets grants, becomes policy advisor, etc).

The scientific part is just using some math while still basing their ideas on idealized unworkable models and unprovable assumptions.

That said, even if all the above was not true, the internal market in China is 1.6 billion people. 4-5 times the US is more than enough to have lots of internal competition.

Heck, there are US-only brands the rest of the world doesn't care at all about -- and that's on a 350 million people market, and they still do just fine.

[ttoinou]

   The scientific part is just using some math while still basing their ideas on idealized unworkable models and unprovable assumptions.

You don't need maths to show that less competition changes the incentive to the point that it could bring down quality of service.

[coldtea]

Yes, but also don't need maths to know that competition can be controlled with 20 ways (and usually is, e.g. US ISPs), or that you can have tariffs AND internal competition.

Or even that you can have a fine quality product at a good price even without competition at all -- e.g. produced by a single vendor, as long as the vendor is so inclined.

[ttoinou]

If competition is controlled then there's less competition and one can expect efficiency to drop down ceteris paribus. Now you have to explain why controlling competition could lead into better quality or cheaper prices. (The only thing I see is that it could let governments keep more money, thus more power ?)

  fine quality product at a good price even without competition at all 

Threat of competition is also a form of competition (for example a software product not protected with patents, anyone could compete so the producer offers good prices)

[Can_Not]

The US is really big, if there's not a mis-configured regulation, adding overseas competition won't really increase efficiency as the perfectly sperical market in a vacuum equation suggests.

[ttoinou]

Maths have nothing to do with economics. I said efficiency as a way of comparing market offer from the point of view of customers (you can picture the formula "quality/price" if you want but that doesn't mean that it is objectively & mathematically defined), meaning that prices go down and/or quality increases

   mis-configured regulation

Do you have examples of good protectionist regulation ?

And no I gave a specific example with software patents so even if the US is big enough it can benefits from outside products

[Can_Not]

If we're talking about efficiency from the customer point of view, I can pay full price for American goods on Amazon but receive garbage-cheap Chinese knock-offs in the mail.