I also learned about the Belgian Congo at school. It was the only colony Belgian had in Africa as Leopold was late to the party. The Belgians were recognised as the cruelest of all the colonisers and with all authoritarianism regimes, the way to control the populous is to either under-educate them or educate them with propaganda.
Amin is the common example of the left of how the British installed a dictator, who was cruel and merciless. However, I prefer to use Mugabe as a better example. He was allowed to take control in Zimbabwe and decimated his political opponents and his country's economy. You don't hear that much of him now. The West turned a blind eye to him and tried to forget what they had allowed to take control.
Do you not see China as an autocracy currently? Xi Jinping is seen by many Chinese as a dictator. I've worked with many ex-pat Chinese people here and they have contrasting views of China. Most see Xi as a modern day Stalin and are nervous about saying anything negative in public about him, even in New Zealand.
Now that's an overreaching arm of control.
I'm presuming you are in the UK - correct me if I'm wrong

. In NZ, Australia and the Pacific, China is seen as the number threat to world peace. They have most governments over a barrel, because of the money that they spend with those countries.
In Africa, the Chinese policy of Belt and Road is putting already impoverished African countries into even more debt, but the Chinese government are extracting their 'interest' payments from natural resources. They are the modern day colonisers.
Along with the abuse of human rights on the Chinese mainland and the offshore territories, it looks like a dictatorship to me.