[Its a Scam to control stupid countries]
It’s not really that complicated - people who are brilliant at amassing power are not necessarily any good at actually exercising that power in constructive ways. North Korea’s Kim Il-sung established a dynasty that has ruled the country for 70+ years while driving its economy into the ground. Some people think the Communist Party has done a great job getting China’s economy off the ground. I’d disagree. The Party has had the benefit of some of the world’s highest quality human resources, both in terms of IQ and conscientiousness.
The Party’s 70-year tenure has more or less coincided with South Korea’s rise from African/Chinese levels of poverty to developed country status. Note that South Korea is almost 4x times more densely populated than China and has fewer natural resources per capita. For instance, China produces 4m barrels of oil per day (vs South Korea’s 0). That’s roughly the same as Iraq and Kuwait, both of which are considered major oil producers. China is also the world’s biggest gold producer. And yet China’s economic output per person is merely 1/3 South Korea’s.
Added to what you said, it has always been a failed tactic of these despots to try and force dependence (i.e., Trans-Siberian Pipeline) when they really cannot control either the vehicle (the pipeline or the “road”) or the end users. And, like you say, all they get are more debts (i.e., Cuba).