The 40th anniversary of China’s “reform and opening up” era comes as the country faces slowing trade growth and widening trade policy challenges. China’s global trade has expanded by 16.1% annually between Jan. 1, 1981 and Oct. 31, 2018. That’s slowed to a 7.7% growth in the past 10 years. The evolution from basic to advance manufacturing in terms of exports may be largely completed too. Apparel has dropped to 7.8% of exports from 22.8% in 1992 while machinery and electronics reached 43.7% from 13.6%. Looking ahead there is room for further growth resulting from new trade deals like t...