We're seeing a continuing and increasing push on the part of the U.S. to incorporate the Balkans into their sphere of influence, and away from possible cooperation with states such as Russia and China, both of which are the driving force behind the emergence of a multi-polar world.
The West is worried about Russian and Chinese projects (i.e. One Belt One Road Initiative, potential pipelines etc.) that could eventually reach the heartland of Europe through the Balkans and then curtail Western influence and control of the region, both economically and politically. This is especially worrisome to the U.S. elite which sees such a future as an existential threat to their global parasitism. Wherever there's potential for an increase in Russian and Chinese influence around the world, a crisis somehow arises, with the blame being assigned to Russia and/or China.
The main reason the West is 'concerned' about the Balkans is due to its role and position on the 'global chessboard'.
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