On February 28, just four days after Russia invaded Ukraine, its state-owned energy giant Gazprom agreed with Mongolia to proceed with plans for one of the world’s largest gas pipelines, aiming to link Russian fields which currently supply Europe to energy-hungry China.  There’s just one hitch: Beijing isn’t yet fully on board.  Gazprom has long been agitating for a deal to supply gas to China via the so-called Power of Siberia 2 pipeline (also known as Soyuz Vostok). Once