Just days after signing the RCEP trade deal, China's president Xi Jinping shocked analysts and the global trade community with his support for the CPTPP - the agreement once thought to be the highest grade trade deal excluding China in existence, and described as 'the anti-China club' by some Chinese commentators. Why would he do this? Finbarr Bermingham sits down with SCMP political economy editors Zhou Xin and John Carter to look at Xi Jinping's motives and how they fit in a broader…