Editor's Note : This is the final installment in a five-part series on Russia's resurgence. Click to read Part 1 , Part 2 , Part 3 and Part 4 . The Central Asian states — Kazakhstan, Uzbekistan, Turkmenistan, Kyrgyzstan and Tajikistan — are important to Russia as buffers from the Islamic world and Asia and as energy and economic partners. Kazakhstan is already integrated with Russia and is part of the customs union with Belarus. Turkmenistan has tried to remain as isolated as possible, and Uzbekistan is actively opposed to Russia's attempts at resurgence. Kyrgyzstan and Tajikistan likely will welcome cooperate with Russia's efforts but internal instability and security issues in both countries will present Moscow with challenges. Kazakhstan Kazakhstan's location makes it integral to Russia's internal security, as it lies on a traditional invasion route from the east and south and thus serves as a buffer from Asian powers.