On February 23, 2013 it became clear that the US would deploy 100 troops to the African country of Niger, in order to assist the French troops in Mali with intelligence (1).
A few weeks before the Niger government approved the building of a new drone base in their country. This would mean the second US drone base on the African continent, after the one in Djibouti, which is used for the assassinations of people in Yemen.
In 2011 president Obama has sent 100 troops to Uganda (2). At (3,4) you can read about various operations have taken place in Africa by the US in the last couple of years.
Although the US dream of a military presence in Africa, called Africom, had been thwarted by African nations for decades, it seems that there is a spread of American troops into Africa.