Plausibility Check: Burundi and Rwanda Become Part of Tanzania (or Tanganyika) After WWII

So right when the decolonization process in Africa is about the start, is it possible for Tanganyika (or Tanzania depending on the time period) to be able to gain control of Rwanda and Burundi without serious opposition? Or was this not possible the moment Belgium gained both territories after WWI?
 
I'm trying to imagine Nyerere being the equivalent to Suharto in that scenario.

Maybe if he’s desperate to gain an excuse to justify himself in power or for some nationalistic cause.

No, neither can I, really, that was more of a joke. Though some of the stuff I've heard about Obote's regime in Uganda after he had been reinstated by Nyerere wasn't entirely flattering.

Yeah if Tanzania did that I wouldn’t be surprised if they decided to annex Burundi and Rwanda.
 
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