The Pentagon is to reorganise its military command structure in response to growing fears that the United States is seriously ill-equipped to fight the war against terrorism in Africa. It is a dramatic move, and an admission that the US must reshape its whole military policy if it is to maintain control of Africa for the duration of what Donald Rumsfeld has called "the long war". Suddenly the world's most neglected con tinent is assuming an increasing global importance as the international oil industry begins to exploit more and more of the west coast of Africa's abundant reserves.

The Pentagon at present has five geographic Unified Combatant Commands around the world, and responsibility for Africa is awkwardly divided among three of these. Most of Africa - a batch of 43 countries - falls under the European Command (Eucom), with the remainder divided between the Pacific Command and Central Command (which also runs the wars in Iraq and Afghanistan). Now the Pentagon - under the Joint Chiefs of Staff and the defence department - is working on formal proposals for a unified military command for the continent under the name "Africom".

This significant shift in US relations with Africa comes in the face of myriad threats: fierce economic competition from Asia; increasing resource nationalism in Russia and South America; and instability in the Middle East that threatens to spill over into Africa.

The Pentagon hopes to finalise Africom's structure, location and budget this year. The expectation is that it can break free from Eucom and become operative by mid-2008.

"The break from Europe will occur before 30 September 2008," Professor Peter Pham, a US adviser on Africa to the Pentagon told the New Statesman. "The independent command should be up and running by this time next year."

A Pentagon source says the new command, which was originally given the green light by the controversial former US defence secretary Donald Rumsfeld, is likely to be led by William "Kip" Ward, the US army's only four-star African-American general. In 2005, Ward was appointed the US security envoy to the Middle East and he is reportedly close to President George W Bush. He also has boots-on-the-ground experience in Africa: he was a commander during Bill Clinton's ill-fated mission in Somalia in 1993 and he served as a military representative in Egypt in 1998. Ward is now the deputy head of Eucom.

America's new Africa strategy reflects its key priorities in the Middle East: oil and counter-terrorism. Currently, the US has in place the loosely defined Trans-Sahara Counter-Terrorism Initiative, incorporating an offshoot of Operation Enduring Freedom that is intended to keep terrorist networks out of the vast, unguarded Sahel. But the lack of a coherent and unified policy on Africa is, according to some observers, hampering America's efforts in the Middle East. US military sources estimate that up to a quarter of all foreign fighters in Iraq are from Africa, mostly from Algeria and Morocco.

Moreover, there is increasing alarm within the US defence establishment at the creeping "radicalisation" of Africa's Muslims, helped along by the export of hardline, Wahhabi-style clerics from the Arabian peninsula.

"The terrorist challenge [has] increased in Africa in the past year - it's gotten a new lease on life," according to Pham.

But it is the west's increasing dependency on African oil that gives particular urgency to these new directions in the fight against terrorism. Africa's enormous, and largely untapped, reserves are already more important to the west than most Americans recognise.

In March 2006, speaking before the Senate armed services committee, General James Jones, the then head of Eucom, said: "Africa currently provides over 15 per cent of US oil imports, and recent explorations in the Gulf of Guinea region indicate potential reserves that could account for 25-35 per cent of US imports within the next decade."

These high-quality reserves - West African oil is typically low in sulphur and thus ideal for refining - are easily accessible by sea to western Europe and the US. In 2005, the US imported more oil from the Gulf of Guinea than it did from Saudi Arabia and Kuwait combined. Within the next ten years it will import more oil from Africa than from the entire Middle East. Western oil giants such as ExxonMobil, Chevron, France's Total and Britain's BP and Shell plan to invest tens of billions of dollars in sub-Saharan Africa (far in excess of "aid" inflows to the region).

But though the Gulf of Guinea is one of the few parts of the world where oil production is poised to increase exponentially in the near future, it is also one of the most unstable. In the big three producer countries, Nigeria, Equatorial Guinea and Angola, oil wealth has been a curse for many, enriching political elites at the expense of impoverished citizens. Angola is now China's main supplier of crude oil, supplanting Saudi Arabia last year. The Chinese, along with the rest of oil- hungry Asia, are looking covetously at the entire region's reserves.

Realpolitik of what suits

Looming over West Africa is the spectre of the southern Niger Delta area, which accounts for most of Nigeria's 2.4 million barrels a day. Conflict here offers a taste of what could afflict all of sub-Saharan Africa's oilfields. Since 2003, the Delta has become a virtual war zone as heavily armed rival gangs - with names such as the Black Axes and Vikings - battle for access to pipelines and demand a bigger cut of the petrodollar.

Oil theft, known as "bunkering", costs Nigeria some $4bn (£2.05bn) a year, while foreign companies have been forced to scale back production after kidnappings by Delta militants. Such uncertainties help send world oil prices sky-high.

The Pentagon's new Africa policy is to include a "substantial" humanitarian component, aimed partly at minimising unrest and crime. But the reality is that a bullish China is willing to offer billions in soft loans and infrastructure projects - all with no strings attached - to secure lucrative acreage.

"It's like going back to a Cold War era of politics where the US backs one political faction because their political profile suits their requirements," says Patrick Smith, editor of the newsletter Africa Confidential, widely read in policy circles. "It's a move away from criteria of good governance to what is diplomatically convenient."

According to Nicholas Shaxson, author of Poisoned Wells: the Dirty Politics of African Oil, "[Africom] comes in the context of a growing conflict with China over our oil supplies."

Africom will significantly increase the US military presence on the continent. At present, the US has 1,500 troops stationed in Africa, principally at its military base in Djibouti, in the eastern horn. That could well double, according to Pham. The US is already conducting naval exercises off the Gulf of Guinea, in part with the intention of stopping Delta insurgents reaching offshore oil rigs. It also plans to beef up the military capacity of African governments to handle their dissidents, with additional "rapid-reaction" US forces available if needed. But - echoing charges levelled at US allies elsewhere in the "war on terror" - there are fears that the many authoritarian governments in sub-Saharan Africa might use such units to crack down on internal dissent.

Raising hackles

The increased US military presence is already apparent across the Red Sea from Iraq, where, in concert with Ethiopia, Washington has quietly opened up another front in its war on terror. The target: the Somalia-based Islamists whom the Americans claim were responsible for the 1998 bombings of US embassies in Kenya and Tanzania. Earlier this year, US special forces used air strikes against suspected al-Qaeda militants, killing scores.

FBI interrogators have also been despatched to Ethiopian jails, where hundreds of terror suspects - including Britons - have been held incommunicado since Ethiopia's invasion of Somalia in December last year, according to Human Rights Watch. The problem with this more confrontational approach in Africa is apparent. "There's definitely a danger of the US [being] seen as an imperial exploiter," says Shaxson. "The military presence will raise hackles in certain countries - America will have to tread lightly."

Nonetheless, the Pentagon is hoping that Africom will signal a more constructive foreign policy in the region and a break with the past. "Politically [Africa] is important and that's going to increase in coming years," says Pham. "It's whether the US can sustain the initiative."

African oil: the numbers

22% of US crude oil imports came from Nigeria in the first quarter of 2007

25% of US crude imports came from Saudi Arabia in the same period

75% of the Nigerian government's income is oil-related

800,000 Nigerian estimate for barrels of oil lost each day through leaks, stoppages or theft by rebels

$2.3bn cost of building Chevron's Benguela Belize platform off the coast of Angola

Research by Jonathan Pearson