In addition to northern Mozambique, East Africa also acquired one-third of the land south of Angola. For this area, Ernst has no intention of developing it right now.
Angola is situated on the Atlantic coast, meaning it's not as easy to intervene as it is in the Indian Ocean. East Africa can exert its naval strength in the Indian Ocean, but it would be less effective in the Atlantic, and it's not feasible to spread out naval forces. What if the British take advantage of it?
Ernst's concerns are not unfounded. Although Ernst dislikes Britain, he has to admit that it is a very pragmatic country. Of course, one could also say it is unscrupulous, willing to forego dignity in order to achieve its goals. Otherwise, it couldn't have become the world's overlord. After all, Britain is just a tiny place, and without some ruthlessness, it couldn't have had Germany, France, Austria, Russia, and America in the palm of its hand.
