If you've the time to watch this theory of world domination, it may explain Chinese (and Russian) expansion,
and the second part,

The blueprint for world domination that spooked America - BBC Ideas
Watch the "The blueprint for world domination that spooked America" video at BBC Ideas. Explore other related content via our curated "Ideas that shaped the world" playlist.
www.bbc.com
and the second part,

The Heartland theory - part two - BBC Ideas
Watch the "The Heartland theory - part two" video at BBC Ideas. Explore other related content via our curated "Ideas that shaped the world" playlist.
www.bbc.com