It is not off topic as I see it. Over all it is still relevant to the thread as the discussion is about orientation of the three among them. To young Chinese born in the 80s and 90s, Yeltsin's days were too early. I am one of the old fart old enough to experience days from late Brezhnev when USSR was kicking around. The trigger? There is no single event. It is many events that triggered the Russians eventual turn. Yeltsin was furious of the west when Yugoslavia (Serbia and Montenegro) was bombed by NATO in 1999 for not giving up Kosovo. But Russia was too weak to do anything besides complaining. Neither could turning to China be any help as China was not as strong as today when its embassy in Belgrade was bombed by NATO in that war. The Russian turning-east is a combination of the accumulated disappointment of Russia to the west's continued containment after the collapse of USSR over a decade and the raising of China's economy and military strength that gives Russia (and for that matter many other countries) a viable alternative. 水到渠成. It is not just because of a single trigger, nor a single president's favor. Note, in my personal opinion, if we are to assign an event to be more important than others, I would say the NATO bombing of Yugoslavia in 1999 was one. It not only shocked the Russians to rethink their approach to the West, but also shocked generations of Chinese to rethink. I still remember the stark contrast of Chinese altitude towards USA of my generation before and after that event. Google it you will see what I am saying.