But the article claims you need &quot;state-of-the-art machinery and cutting-edge computerized measurement equipment with pinpoint precision to produce, not to mention the ability to produce the high-quality steel material of which it is made.&quot;<p>None of this was available post-WW II, like the advanced steel alloys the article talks about. China&#x27;s industrial capacity is more advanced than the US&#x27;s was in the 1950&#x27;s and if China does not produce those little metal spheres there must be something else at play.<p>My guess would be that thanks to modern production processes, a competitor with older machinery would not stand a chance in the marktplace and investing in the production of those balls is economically not very attractive because margins are already razor-thing. But I&#x27;d like to read from someone who actually knows.