They all happen to be former Soviet republics without their own energy resources.

When the capital development of a country becomes a by-product of the activities of a casino, the job is likely to be ill-done. — John M. Keynes

You can also compare the net oil imports to a country's currency reserves. It turns out that US and some European countries don't have a very thick cushion to protect themselves form rising oil prices, but the economic impact (a function of GDP) is not too dire. However, Belarus and Tajikistan are vulnerable both because they import a large amount of oil relative to their GDP but also relative to their reserves, so they can't shield the blow and it's going to hurt. I'll leave the geopolitical implications to you...

When the capital development of a country becomes a by-product of the activities of a casino, the job is likely to be ill-done. — John M. Keynes