> In a notice published online the US Department of Commerce said it refused Intel's application to export the chips for Tianhe-2 and three other Chinese supercomputers because the machines were being used for "nuclear explosive activities".

http://nextbigfuture.com/2015/04/us-will-make-180-petaflop-s...

Oh no, they're using their supercomputers to do nuclear research? That's horrible. Who would do such a thing?

The given reason is all bullshit, and they must think we're all morons if they expect us to buy it. If anything it's retaliation for some IP theft or some silent trade war going on between China and the US. It's certainly not because the US gov is "shocked" that China uses its supercomputers to do nuclear research.

Simulating nuclear explosions in software has been a major response to treaties that forbid nuclear tests. As I think you were ironically pointing out, it's common now.

It might be hard for the U.S. government to effectively prevent the Chinese government from doing these simulations, but it's plausible to me that the U.S. government would still want to see the Chinese government hindered in nuclear weapons simulations.

It is interesting to point out that the last few nuclear tests were to test the supercomputer simulations.

If you want to sell technology products in the China market, you need to transfer technology to China, such as setting up a R&D centre. Everyone answers to sales.

Then comes Machiavellian management strategies that demonstrate large companies are not idiots, and withdrawal of such scheme 2-5 years later, while still holding sales lines in China.

Source: Have worked on both sides of the technology transfer equation.

Naturally, the people who are modding you down are conspicuously silent on why it's necessary or even desirable to make it harder for China to simulate nuclear weapons.

Who said anybody was shocked?

To prevent them from building a powerful supercomputer.

No, seriously.