* Visits to Senegal, South Africa, Tanzania
* Mandela's health may steal spotlight
By Mark Felsenthal
WASHINGTON, June 25 (Reuters) - It is a comparison President Barack Obama may not relish: when it comes to Africa, he's no Bill Clinton. Or even George W. Bush for that matter.
Obama makes his first extended trip to Africa on Wednesday. After the sky-high expectations raised by his election in 2008, Obama now faces the prospect of trying to convince Africans that the United States has vital interests there that it intends to safeguard and pursue.
"The African leaders, the African public have been wondering where the U.S. president has been," said Ben Leo, global policy director for the anti-poverty group ONE.
"This trip has been designed to address some of those perceptions, those concerns, hopefully reset the engagement trajectory over next couple of years."
Obama's trip risks being overshadowed by the deteriorating health of South Africa's national hero and revered former leader, Nelson Mandela, who is approaching his 95th birthday.
Mandela's decline could dwarf other topics. Madiba, as he is known by his clan name, is adored by most of South Africa's 53 million people as the architect of the 1994 transition to multi-racial democracy after three centuries of white domination.
Mandela spent his second week in a hospital, where his condition was described as "critical."
The White House has said Obama will defer to the wishes of the Mandela family with regard to any meetings.
"We'll be in touch with them," said White House foreign policy adviser Ben Rhodes. "If he has an opportunity to see the family in some capacity, that's certainly something that we may do."
Obama may also face questions about the exposure of classified information by former U.S. government contractor Edward Snowden, which has forced the president to defend widespread government surveillance of Internet and phone data.
The furor over Snowden's disclosures could drown out issues Obama wants to spotlight on the trip, particularly Africa's potential as a business and trade partner for the United States.
Still, Obama's weeklong visit may afford him a chance to reverse some of the criticism that his administration has failed to launch any of the grand health or trade initiatives in Africa that his two predecessors accomplished.
In the absence of U.S. involvement, other countries, particularly China, have aggressively pursued business opportunities on the continent.
"This is a place where the United States needs to be present, and we're very pleased that early in the second term, we can send a signal of increased U.S. engagement through this trip," said Rhodes.
SHADOW OF BUSH, CLINTON
Critics of Obama's Africa policy point to George W. Bush's program to combat HIV/AIDS in Africa, with an initial commitment of $15 billion over five years when it as launched in 2003. As a result, the United States is credited with directly supporting antiretroviral treatment for more than 4 million people.
"George kind of knocked it out of the park," the Irish rock star Bono, an activist for development causes, said last year.
Bush is also praised for initiating the Millennium Challenge Corporation, a foreign aid agency that provides assistance, if a recipient nation can meet good government criteria, for anti-malaria initiatives and for forgiving debt.
Before him, Bill Clinton generated enormous goodwill by becoming the first American president to make more than one trip to Africa and for signing the Africa Growth and Opportunity Act, which dropped trade restrictions on more than 6,000 exports to America from 35 African countries.
Clinton was also close to Mandela and supportive during South Africa's transition from white-minority rule to its first free election in 1994.
"Africans still consider Clinton their president," Mwangi Kimenyi, director of the Africa Growth Initiative at the Brookings Institution, recently told reporters.
Obama has been preoccupied with winding down two foreign wars and the worst financial crisis in the United States since the Great Depression.
While the United States' attention has been focused elsewhere, China's trade with Africa has ballooned from about $10 billion in 2000 to $166 billion in 2011. Much of that is an exchange of African minerals for Chinese manufactured goods.
Even so, the elation many Africans felt when the United States elected its first black president, one whose father was a Kenyan, has been replaced by puzzled disappointment.
"We are witnessing a gradual and continuous U.S. retreat from Africa," Sudanese-born telecommunications magnate Mo Ibrahim said in a speech in Washington in April.
"We don't understand that. The U.S. has been a great friend all these years, but as soon as Africa found itself starting to move up, the U.S. is really disengaging."
Obama's trip will take him to Senegal, South Africa and Tanzania, all countries with functioning democracies that will help the president make the point that democratic institutions are a building block for sustained economic growth.
In the runup to the trip, the Obama administration has filled two important Africa policy jobs. It named Linda Thomas-Greenfield as assistant secretary of state for African affairs and former Senator Russ Feingold as special envoy to the conflict-torn region that includes Uganda, Rwanda, Burundi and the eastern portion of the Democratic Republic of Congo.
While he is there, Obama will visit Goree Island in Senegal, from where Africans were sent into slavery in the New World, and Robben Island in South Africa, where Mandela was imprisoned under white apartheid rule.
Obama will bring an entourage that includes his trade representative and the heads of the U.S. Export Import Bank and the Overseas Private Investment Corp.
"First and foremost, the big new theme will be elevating U.S. economic engagement with Africa, getting a broader swath of the U.S. private sector interested and educated on the opportunities on the continent," said Jennifer Cooke, director of the Africa Program at the Center for Strategic and International Studies. (Editing by Christopher Wilson)