After the disintegration of the Soviet Union, why are the fates of Kazakhstan and Ukraine so different?

Kazakhstan is a remote place with backward economy. During the Soviet era, it was the younger brother who followed the older brother. After the disintegration, I honestly joined the Russian Federation and queued up to participate in the Shanghai Five countries. I didn't show off and there was no big problem-of course, the domestic situation is also very general now, which is also a passable level.

Ukraine's position is key, its economy was once among the best among Soviet allies, and its relationship with the Central Committee of the Communist Party of the Soviet Union was also full of grievances and enmities. After the disintegration, it was the happiest, but no matter how strong the capital is, it will not last for decades. In the last decade, even the civil war has been fought. With such a poor political level, Ukraine's domestic politics can't be done well, and it has to ride the wall to gain benefits in the competition between Russia, the United States and Europe, which is doomed to find fault and swell all the time.