As Prime Minister Meles Zenawi of Ethiopia concludes his 21st year of rule, and as rumours of his illness and possible demise abound, many are wondering what the future holds for the country.

There is significant anxiety within Meles' inner circle about who will take the reins of power if the prime minister passes away and increased speculation amongst his enemies despite the regime barring the media from reporting on Meles' health.

People are questioning whether succession will be easy and smooth or slow and difficult; whether the new leadership will be willing to share power with the growing opposition and many ethnically-inspired movements in the country; who the new rulers might be; and whether the ruling Ethiopian People's Revolutionary Democratic Front (EPRDF) coalition will survive the end of Meles' paternalistic rule. As of now, however, questions are abundant but answers are few.

Ill at ease

Speculation about Meles' health began in 2009, when he was reported to be receiving treatment for an unspecified illness in the United Arab Emirates. And rumours resurfaced again recently after the prime minster missed a number of public events, including the recent African Union summit in Addis Ababa and a parliamentary debate on the budget on July 8.

As the prime minister's health has visibly deteriorated and he has disappeared from the public eye for over a month and half, concern has grown not just about Meles' wellbeing but about what might happen in the eventuality of the highly influential leader's death. For two decades, Meles has dominated the Tigrayan People's Liberation Front (TPLF), the group responsible for the overthrow of Colonel Mengistu Haile-Mariam's 17-year dictatorship in May 1991 and the party which forms the main part Ethiopia's ruling coalition, the Ethiopian People's Revolutionary Democratic Front (EPRDF).

Should the PM die or step down for health reasons, some possible successors as PM include Hailemariam Desalegn (the hand-picked deputy prime minister and foreign minister); Tewodros Adhanom (the health minister and close confidant of the Meles); and Azeb Mesfin, (an MP, member of the EPRDF's powerful nine-member executive committee, and Meles' wife). It is doubtful whether any of these individuals would be capable of holding together the complex coalition that makes up the EPRDF.

Military strength, US support, and individual charisma

The stability of Ethiopia's regime is anchored on the strength of its military, support from the US, and the individual intelligence and charisma of Meles.

Meles has used his security apparatus effectively to hang on to power. His violent crackdown on demonstrations in 2005 following the allegedly rigged election was indicative of this, while the 2010 elections cemented one-party rule with a vengeance in the form of repression, quashing dissenting voices and shutting down of independent media.

Furthermore, as dissident groups have emerged, Meles' regime has arrested and sentenced to long jail terms several dissidents, journalists, Oromo nationalists and Islamic activists, classifying them as terrorists.

While opposition and discontent have been growing in Ethiopia, dissident groups are relatively weak despite the noise from diaspora media and exiled Ethiopians, and Ethiopia's security apparatus is highly vigilant of such groups. The demise of Meles, however, could embolden the opposition, accentuating ethnic and religious cleavages in the country and disturbing the status quo.

Currently, a sustained, large Muslim protest has become a new source of worry for the regime. The government attributes the unrest to infiltration from Saudi Arabia, Sudan and Somalia by Salafists and Wahhabists, but this attempt to externalise the issue is disingenuous. Ethiopian Muslims who number anywhere from 30-50% of the population have historically been marginalised and grievances could undermine political stability. It seems fairly likely therefore that Meles' successors will continue to be dependent on the TPLF-dominated military.

It also seems likely that Ethiopia will continue to enjoy the support of the US. Ethiopia is currently the biggest recipient of official development assistance in sub-Saharan Africa and the second biggest recipient in the world. Despite his Marxist roots, Meles has attracted Western investment and foreign aid, and has so far managed to hold together a difficult country racked by decades of war, famine and economic devastation.

One reason Ethiopia attracts so much Western support is that Meles is the pillar of Obama's campaign in the Horn of Africa. Having established himself as an indispensable ally of the West in the fight against terrorism, Meles has enjoyed continuing American support in the face of his obdurate internal policies and effective isolation of Eritrea in the UN Security Council, Intergovernmental Authority on Development (IGAD) and the African Union. Ethiopia is seen as a vital ally in the "war on terror", a bulwark against Sudan, Eritrea and Somalia.

Despite its concerns, the US is reluctant to send its own forces to stabilise Darfur, Somalia, and the Democratic Republic of the Congo. It thus relies on local strongmen such as Uganda's President Museveni, Rwanda's President Kagame, and Meles. In return, suppression of dissent in Ethiopia is glossed over, unlike in President Robert Mugabe's Zimbabwe or in President Omar al-Bashir's Sudan. For the US, Ethiopia is a military bridgehead to contain al-Qaeda infiltration in Somalia, the rest of the Horn and even across the Red Sea in Yemen. This support is likely to continue.

What seems most uncertain at the moment is whether, without Meles' charisma, the leader's successor or successors will be able to galvanise the support of key party leaders and technocrats within the government.

Challenges for the future

If Meles were to pass away or pass over the reins of power, the challenges for his successor will be considerable.

For example, in spite of a reported average growth rate between 8-11% since 2000 - partially a result of foreign investment in the country's agricultural and manufacturing sectors - Ethiopia's economic challenges linger. Theft from state enterprises and participation in the black market, including widespread graft, is common. Meanwhile, increases in imported global food and fuel prices, rapid expansion of the broad money supply, and a large devaluation of the birr has led to high inflation in recent years. Furthermore, large and persistent government deficits and the absence of virtually any stabilising fiscal and monetary policies have accelerated a downward economic spiral.

Another critical problem a post-Meles Ethiopia will have to grapple with is the powerful military. The military has acquired unprecedented levels of power under Meles and it will continue to be a decisive player. The forces are dominated by Meles' ethnic group, Tigrayans, and any attempt to create a truly representative national army may prove difficult.

Attempts to undermine TPLF power and authority will undoubtedly be resisted by Meles' inner circle as serious threats. The military has significant control and influence in key economic sectors in Ethiopia and it will be tough to dislodge the forces from these activities and limit its role to a strictly military one.

The military's role will also be affected by ethnic conflicts which may worsen after Meles. Meles' rule has been characterised by repression, war and interference across borders, which has engendered some resentment among different groups including the former ruling classes of the Amhara ethnic group. And tension along the disputed frontier with Eritrea has increased recently, following a cross border raid by Ethiopian forces, the first known incursion into Eritrea since 2000.

Ethiopia's new leaders will also have to grapple with the country's regional frictions. Under the EPRDF, Ethiopia was officially declared a federal state though the strong centre never really allowed for the true spirit of federalism to emerge. And grievances of regions believing they are not getting their fair share, commensurate with their resources, remains unresolved. There is a long list of regional claims of mistreatment by the centre including issues such as misuse of river waters and the "leasing" of indigenous land to foreign capitalists. Gambela, on the border with South Sudan, is possibly the region worst affected by land leasing and displacement. The government has earmarked almost half of the region to become commercial farms, and since 2008 a number of foreign companies have leased a total of 225,012 hectares in the state.

In theory, the constitution contains provisions that protect the rights and aspirations of regions, but the high-handedness of the EPRDF regime has undermined regional autonomy, making a mockery of the concept of true federalism. Grievances around these issues will be awaiting Meles' successor.

Meles' record as prime minister has been complex and mixed. He has been criticised for his human rights record yet has a reputation for being technocratically focused on achieving pro-poor sustainable development. He has led his country to a level of modernisation it has never known yet followed in his predecessor's footsteps by withholding food aid against opposition. He has been the central figure in Ethiopia's fate over the past two decades. It is little wonder that many are concerned about what a post-Meles era will bring.

Yohannes Woldemariam is an academic and writer. He grew up in Ethiopia but now lives in the United States, teaching International Relations and Comparative Politics at Fort Lewis College in Colorado. He is also adjunct graduate faculty in Comparative Public Policy at the University of Colorado in Denver.