What began as a reaction to the jihadist activity in Mali in 2012 has steadily expanded across the belt of the Sahel region. In this semi-arid climate, just south of the Sahara, some 4,000 French troops are combatting jihadist forces in five African countries. Not since the colonial era has France shown this level of economic and military commitment in Africa. But, what exactly is this conflict about and why do the French feel the need to get involved.