LONDON: What is driving the explosion of Chinese exports, which hit almost US$4 trillion last year? That question is creating deep angst among non-Chinese policymakers amid fears of a second “China shock”. And now a row about this has erupted between some Chinese economists and the OECD. This echoes repeated American and European complaints that China is using “unfair” tactics to undercut rivals. But Chinese economists such as Kai Guo argue that “subsidies are no longer the most convincing explanation for Chinese firms’ growing competitiveness”.