And that's where it stops. Ma made a general observation and that's it. Historically countries who trade less tend to be hostile toward each others, while countries who trade in bigger volumes are friendly.
Also Ma isn't saying or implying "keep the trade deficit". He says "keep trading. period" (a surplus or a deficit, doesn't matter in the context of his argument.) By the way it's weird that people seem to think it's China's problem that the US have a trade deficit with them. The deficit can be solved by the US selling products and services to China. It's the US' problem to find what to sell. And only the US can solve it.