Great, who would pay for that ?
The US, for example, has sunk trillions of dollars into Iraq and Afghanistan, depolyed tens, if not hundreds of thousands, of soldiers and it doesn't have a whole lot to show for it... It has also been involved there for close to 2 decades. How much $$$, lives, and decades would it take to clean up Africa ?
Africa is a ticking time bomb. You have a continent that has an exponentially growing population. This populace is largely uneducated, frequently holds bizarre and radical beliefs, and is facing significant levels of poverty. And pretty widespread political instability. You also have a large cohort of unemployed, bored and impoverished young men who have very little to lose. This is the perfect recipe for these insurgent groups. All they need is numbers- which they have plenty of. Mow ten of them down and 20 will pop back up to take their place- they're like a hydra. Short of committing large scale annihilation or genocide I fail to see how this can be stopped by outside actors.
You saw this happen on a miniature scale in Iraq when some "geniuses" decided to disband Saddam's army and leave about a million arab men unemployed. Unsurprisingly it led to a massive insurgency. And despite the amount of troops and money America poured in it wasn't exactly able to destroy it. Iraq today is hardly an example of a stable state. I'd argue that Iraq today is worse off than it was under Saddam.