Late to the party, Obama seeks bigger U.S. Africa role

* "Son of Africa" U.S. leader chided for lukewarm engagement

* China, others seen leading the charge into rising Africa

* Many U.S. companies chasing competitors on the continent

* Support for local armies, but minimal U.S. "boots on ground"

By Aaron Maasho and Pascal Fletcher

CAMP LEMONNIER, Djibouti/JOHANNESBURG Aug 3 (Reuters) - Ask Major-General Wayne W. Grigsby Jr., the top U.S. military officer in Africa, how he thinks U.S. and European-backed African troops are faring in their war on Islamist militants in Somalia, and his answer comes back smartly: "Pretty darn good!".

But when "son of Africa" U.S. President Barack Obama hosts 50 African leaders in Washington this week, the admiration may be less than mutual. Many Africans feel America is lagging behind China and others in its engagement with their continent.

The Aug. 4-6 U.S.-Africa Leaders Summit, billed by U.S. officials as a first-of-its-kind event, looks like a belated imitation of Africa gatherings hosted in recent years by China, India, Japan and the continent's former colonial master Europe.

The world's richest nation has been slow coming to the party of an economically rising Africa, long dismissed as a hopeless morass of poverty and war, but now offering investors a huge market for everything from banking and retail to mobile phones.

"The United States has fallen perhaps a little bit behind in the race to win African hearts and minds. So I think this is an attempt to compete with the likes of China and the European Union," said Christopher Wood, an analyst in economic diplomacy at the South African Institute of International Affairs.

The top U.S. diplomat for Africa, Linda Thomas-Greenfield bridles at suggestions that the Obama administration is playing catch-up. "Absolutely not," she said.

"Our relationship with Africa is a very strong historic relationship ... We see this as an opportunity to reaffirm that to African leaders," she said in a pre-summit conference call.

CHINA RACES AHEAD

China overtook the United States as Africa's biggest trade partner in 2009. Its leaders have criss-crossed the continent, proffering multi-billion dollar loans, aid and investment deals.

From Malabo to Maputo, Africa is studded with signs of Beijing's diplomatic and commercial outreach: Chinese-built roads, bridges, airports, stadiums, ministries and presidencies.

Since 2009, Obama, despite his African blood through a Kenyan father, has been a far less frequent visitor. His first substantial trip to the continent was only made last year.

Washington's many embassies in Africa - imposing concrete fortresses built to protect against angry mobs or terrorist attacks - project a cautious engagement from an Obama administration highly sensitive to a home public which has no appetite for overseas interventions after Iraq and Afghanistan.