He means the One China Policy. But CogitoCogito is right. China is only be "contained" by Taiwan in the hypothetical circumstance of a war; during peace time they obviously have no trouble sending ships around the world and are not contained in any sense. And the only reason they haven't been able to bring Taiwan into the fold is because they keep making psychotic violent threats. All China needs to do to completely resolve any problems with Taiwan is stop being nuts.

China obviously doesn't want the matter resolved peacefully, if at all, because they use this conflict for internal control.