NIAMEY, Niger (Reuters) - Sent from China to hunt for oil under the Sahara desert, Wenhui Tan looked distinctly uneasy as the conversation turned to security fears ranging from the spread of Islamic radicalism to cold-blooded banditry.
"What have you heard?" asked the China National Petroleum Corp executive, lighting a cigarette and gesturing at a map of the West African desert country Niger, with two huge exploration blocks outlined in black ink.
The United States shares his concern as it ventures into remote corners of West and Central Africa in search of alternative oil supplies to the turbulent Middle East that could also act as counterweight to OPEC's monopoly power.
The world's biggest energy consumer hopes the African region will provide up to a quarter of its oil imports within a decade, up from 14 percent now, and is working to guarantee stability in one of the most volatile parts of the planet.
From coup attempts inspired by dreams of petrodollars to concerns over Islamic extremists, political anarchy, civil war and piracy, the region around the Gulf of Guinea is seething with tensions that would faze the most intrepid investor.
"We are in no position to endure a serious oil supply disruption from the Gulf of Guinea today. The global oil market is stretched to capacity," said David Goldwyn, a former assistant energy secretary in the Clinton administration and head of a Washington-based strategy think tank.
"We are not ready for trouble, but trouble is on the horizon," he told a U.S. Senate committee earlier this year.
Washington is particularly concerned that militant Islamists may gain a foothold in its new oil haven, where policing is often lax, millions of youths are unemployed and the sheer size of territories makes maintaining full control almost impossible.
"It's a good place for people who want to be left alone to operate outside the reach of the law -- to go unnoticed, to take time to recruit, to regroup," General Charles Wald, deputy commander of U.S. European Command (EUCOM), told Reuters.
Fearing that militants may exploit the lack of authority in vast countries on the southern fringe of the Sahara, Washington has sent Marines and special forces to train troops in four states regarded as a secondary front in its "war on terror."
The State Department's Trans-Sahara Counter Terrorist Initiative (TSCTI) has trained troops in former French colonies Niger, Mauritania, Mali and Chad to act on U.S.-supplied intelligence about the movements of suspected extremists.
Privately, some officials acknowledge that the main concern in the region is protecting Nigeria, the continent's biggest oil producer, the region's only OPEC member and the main destination for U.S. investment in sub-Saharan Africa after South Africa.
Crude from Nigeria accounted for almost 9 percent of U.S. oil imports in 2003 -- averaging 838,000 barrels per day according to the Energy Information Administration -- a figure which is expected to increase over the next decade.
"It's one of those nations that's teetering right now, economically, socially and militarily. It's in everybody's vital interests to make sure it teeters on the right side and doesn't fall off," said a senior U.S. military official.
A report published in August by the Congressional Research Service said there was no evidence of international terror groups working in Nigeria but voiced concern that could change.
"It is possible that such actors could begin to view Nigeria, particularly its oil production and export facilities, as a strategic target both for armed attack operations and as a base for building political support," the report said.
"The potential for such an outcome is suggested by a comment attributed to Osama bin Laden (news - web sites), who, in a taped message, labeled Nigeria ... as being among 'the most qualified for (religious and political) liberation'," it said.
An uprising by rebels demanding autonomy for the oil-rich Niger Delta this year will have done little to calm nerves.
FAILED STATES AND FUNDAMENTALISTS
There are also fears that the rapid implementation of Sharia law in Nigeria's northern states could promote stricter versions of Islam elsewhere, especially in the Sahel, traditionally a religiously moderate region on the southern edge of the Sahara.
"There's a lot of trouble (in Nigeria). We're keeping an eye on it," Niger's Defense Minister, Hassane Souley, told Reuters.
Some U.S. officials and analysts, mindful of al Qaeda training camps in Afghanistan (news - web sites) and networks in Pakistan, fear West Africa is a fertile hunting ground for religious radicals.
"There are a large number of Pakistani preachers all over Mali. There are some in Guinea, some in Niger and I believe some in Nigeria as well," said Mike McGovern, acting West Africa project director for think tank International Crisis Group.
Analysts are split on whether religious radicalism will necessarily translate into a threat against Western interests, but point out that the oil infrastructure in much of the region was set up with no serious threat of sabotage in mind.
"The naval forces of the West African states do not have the capacity to protect oil rigs and facilities. The area is a soft target for any terrorist willing to attack," Goldwyn said, adding that Nigeria's coast was second only to the Malacca Straits between Indonesia and Malaysia for piracy.
The domestic stability of some of the region's most promising sources of crude is also a concern and only likely to get more volatile as political factions argue over oil wealth.
The lure of offshore deposits in sub-Saharan Africa's third-biggest producer, Equatorial Guinea, triggered a failed coup attempt in March. Sao Tome e Principe -- a tiny archipelago believed to hold large oil reserves -- was rocked by a coup last year, sparked chiefly by concerns about future oil wealth.
Nigeria and Cameroon are bickering about who owns the potentially oil-rich Bakassi peninsula. The region's newest oil-producer, Chad, had to crush an army mutiny this year and Mauritania, due to start pumping oil next year, has stifled three military uprisings since June last year.
None of which gives CNPC's Tan much ground for optimism as he embarks on his quest for crude under the Niger desert, sandwiched between oil majors Nigeria and Libya.
"In other countries the government will support you with the army and soldiers. Here you have to be self-sufficient," he said. "But at least it's more secure than Nigeria." (Additional reporting by Mark Trevelyan in Berlin and Toby Reynolds in London)