Five years after Ethiopia invaded Somalia, with U.S. backing, Kenya has sent its troops and tanks into its lawless neighbor with a similar objective: setting up a border buffer zone to block Somalia's jihadists.

The Kenyans no doubt had the blessings of the U.S. administration of President Barack Obama as well, for helping the Pentagon fight global terror is the name of the game.

But so is securing the emerging energy boom in West and East Africa, along with other minerals in what is becoming a strategic contest between the United States and China, widely seen as the Americans' paramount rival in the years ahead.

Africa's exports of oil to the United States, largely from Nigeria and the dictator state of Equatorial Guinea, are roughly equal to those of the Middle East.

The Nairobi government's mini-invasion of southern Somalia is aimed in part at curbing the anarchy there, which increasingly threatens to spread to Kenya and which has eluded the combined efforts of the Western powers.

Kenya can now look forward to U.S. largesse by actively helping the Americans contain, if not crush, Somalia's jihadist al-Shabaab, linked to al-Qaida and deemed a direct threat to the United States by the administration.

In the meantime, Obama has sent a 100-man detachment of U.S. Special Forces to Uganda, supposedly to help the Kampala government, which has played a key role in propping up the shaky, Western-backed Transitional Federal Government installed in Mogadishu by the Ethiopians in 2006.

Since then, Ugandan President Yoweri Museveni has contributed several thousand troops to the heavily armed African Union "peacekeeping force" that keeps Somalia's corruption-riddled TFG in place.

Sending elite troops to crush a brutal warlord, a murderous Christian crackpot named Joseph Kony who heads the Lord's Resistance Army, which has plagued Museveni's regime for a decade or more, may be an expression of the Pentagon's gratitude.

By all accounts, the LRA is on the ropes, so the justification for U.S. military support seems rather odd.

But recent oil strikes in that land-locked Kenya may have had a lot more to do with the decision to send in the forces, as would the creation of the Africa Command in 2007 to coordinate U.S. military operations across the continent.

A major oil strike was made around Lake Albert in western Uganda in 2006, and geologists say it contains at least 2 billion barrels.

Only 25 percent of the region, which includes the Democratic Republic of the Congo, has so far been explored, and some reports say there could be up to 6 billion barrels there.

Uganda expects to start producing an initial 200,000 barrels per day in early 2012.

"Among American interests are the increasing importance of Africa's untapped natural resources, particularly energy resources and mounting concern over violent extremist activities especially in the Horn of Africa, and other potential threats by revolutionary parties and 'under-governed spaces' such as maritime piracy and the illicit trafficking of diamonds, gold and platinum," observed political scientist Professor Naimah Achim Bucha of Kampala's Makerere University.

"In disguise, there is concern for Africa's many humanitarian crises, armed conflicts and more general challenges, such as the devastating effect of HIV/AIDS.

"This one in particular is used as a cover for U.S. (non-governmental organizations) to penetrate Africa and gain access to the all-important information that can facilitate U.S. access to natural resources," Busha added.

"The truth is that Africom is there for the militarization of Africa and for the other purpose of elbowing out all U.S. competitors from the continent, China and Russia included."

China is now Africa's largest economic partner. Trade in 2010 totaled $114 billion, up from $10 billion in 2000.

The African Development Bank Group estimates that Chinese companies accounted for 40 percent of all corporate contracts in Africa signed in 2010. By comparison, U.S. firms managed 2 percent.

In September 2010, Ghana signed loan agreements with China for infrastructure and other projects worth $15 billion -- just as the West African state began producing oil from a major new field.

In Angola, a key oil supplier for Beijing, Chinese banks extended loans and other financing totaling around $9 billion in 2010, the African Development Bank says.

The Americans are belatedly trying to catch up but the Chinese are years ahead of them.