Russia is an aggressive presence in the Baltics because it fears invasion from the West.

There’s no denying the fact that Russia is enormous. Covering a sprawling 6 million square miles and containing eleven different time zones, Russia is by far the world’s biggest country.

So what keeps Vladimir Putin, the president of Russia, tossing and turning at night? It’s one particular stretch of land that somewhat resembles a slice of pizza.

Beginning in Poland, this particular pizza-slice-shaped wedge extends southeast to the foot of the Ural Mountain range, and northeast to Russia’s capital city of Moscow.

What keeps Putin particularly worried is that this area of land is part of what’s called the North European Plain, which stretches from France across Belgium, the Netherlands, Northern Germany, Poland and ends at the Russian Urals. As the name suggests, this area is flat and makes the European gateway to Russia vulnerable and difficult to defend.

Any country within the North European Plain could conceivably send an army across the flatlands and directly into Moscow. As Putin knows all too well, this is exactly what has happened to Russia throughout its history.

During both world wars, this is the path the Germans took in their military campaigns. But that’s not all – since 1812, invaders from the Northern European Plain have attacked Russia an average of once every 33 years!

For generations now, Russia’s strategy for neutralizing the threat from the North European Plain has been to control Poland and all the Baltic states that lie between it and Russia, which include Lithuania, Latvia, Estonia and Belarus.

These are the nations that make up the meat of that pizza slice, so to speak. While the wedge stretches 2,000 miles from north to south at its easternmost section, it’s only 300 miles wide around Poland and the Baltic states. If Russia can station a strong defensive front here, it can more easily hold off potential Western invaders.

Unfortunately, this means the Baltic states are likely to continue having a rough go of it.