Geography
The Role of Buffer States in Mediating Regional Power Rivalries
Quick fact
Historically, buffer states have been surprisingly effective at preventing direct great-power wars: for example, Afghanistan served as a buffer between the Russian and British empires during the 19th century's 'Great Game,' and no direct war broke out between them.
Why this is interesting
You've probably seen maps where two rival nations appear to have a small country sitting between them—like a cushion. But can a tiny state really prevent two giants from crashing into each other?