Interesting comparison, but it's not really the same situation. In the case of the US and Canada there were large border regions that were essentially frontier

Interesting comparison, but it's not really the same situation. In the case of the US and Canada there were large border regions that were essentially frontier societies with little protection offered by the state, but the major population centres and the areas between them were generally safe. And as time went on, the expansion of both countries were driven in large part by the expansion of their armed forces and the gradual extension of control over more and more of the country. Aside from a few hardy settlers, there were no large population groupings living in areas in which the state had not yet established a basic level of control. The societies expanded their territory only as the security umbrella which protected them grew larger. For many African countries, such as the DRC, this is not the case. They have inherited borders and population groupings that date from colonial eras and have more to do with arbitrary lines drawn on a map than the actual ability of each country to enforce or protect them. As a result there is seldom a single point of origin from which to begin the creation of a security umbrella and then expand outwards; instead they have to individually try to secure a number of cities and towns situated far apart from each other while trying desperately to get a hand on the largely undeveloped and un-patrolled areas in between. To use the DRC as an example, the national army has virtually no control over the land between Kinshasa, the capital, and cities like Goma and North Kivu. There is no proper level of internal security. To be fair, your point about the quality (or lack thereof) of African security forces is valid. There's no doubt that if more African armies were well-trained, disciplined and professional they would be able to make far more effective use of the limited resources available to them. Unfortunately, most are as useless and corrupt as the political hierarchies governing their countries. But my point was that even with well-trained forces, the vast distances across which many African countries stretch make an already difficult situation so much harder to deal with on the tiny budgets most African countries have available. And that even those who do attempt to get their act together are dragged down by the fact that trade, the one thing that could lift them out of poverty, is often severely restricted by geography.