Ethiopians could be forgiven for their scepticism when their new prime minister, Abiy Ahmed, promised sweeping reforms last spring. The ruling Ethiopian People’s Revolutionary Democratic Front coalition which appointed him toyed with change in 2005 – only to revert to its usual autocratic form. Now wariness has been replaced by genuine enthusiasm; the transformation is happening at dizzying speed. But the obstacles and perils are also clearer.

Mr Abiy, 42, has followed symbolic shifts with more substantive action. His president, chief justice and half of his ministers are female. He freed thousands of political prisoners and journalists, before arresting senior officials for human rights abuses and corruption. He overturned bans on opposition groups and invited an exiled dissident home to head the election board. The next polls are scheduled for 2020. Last time, not one opposition MP was elected. Mr Abiy’s overtures to Eritrea led to the end of a long-running conflict. He oversaw the meeting of South Sudanese leaders that produced a fragile but desperately needed peace deal. This – along with Eritrea’s ensuing rapprochement with Somalia and Djibouti – led the UN secretary general António Guterres to speak of “a wind of hope blowing in the Horn of Africa”.

Yet Ethiopia has seen an alarming rise in multi-faceted ethnic violence. Over a million citizens were displaced last year. State controls have loosened in a country with entrenched divisions and rivalries: the EPRDF has heavily promoted ethnic identity as the basis for mobilisation, including through the complex system of ethnic federalism it introduced. Some fear the security apparatus does not know how to tackle clashes by any means other than the old, brutal methods. This autumn, following criticism over its handling of unrest, the government detained over a thousand in military camps for “rehabilitation”. There are fears Mr Abiy’s plans for overhauling the economy, including privatising state enterprises, may enrich some but hinder progress on poverty reduction. Any perception some are profiting from the sell-off of state assets could be inflammatory.

Too much rests upon Mr Abiy at present. One concern is that charismatic leadership can slide into unchecked personal power. Another is that any leader seeking change must battle powerful interests. The EPRDF is riven by competition between its four ethnically based parties and institutional and personal rivalries. The chair of the Tigray party recently accused Mr Abiy of “seeking to bring Tigrayan people to their knees”. His premiership has seen a grenade attack on one of his rallies and the arrival of angry soldiers at his office; he says they wanted to kill him. His defusal of that situation hinted at his adroitness; his background in the military has also surely been useful to him. Given that the EPRDF had until last year been Tigray-dominated, his rise as an Oromo (with an Amhara mother), reflects his skills as a politician as well as the Oromo protests which triggered his predecessor’s resignation.

But with only a year until elections are due, there is still no proper political roadmap from the government. Swift progress is needed in reforming repressive laws. Some would like to see a new constitution dismantling ethnic federalism, though most suspect prudence will restrain Mr Abiy from such a wholesale change. His record to date is unquestionably impressive. But the developments he has set in train in Africa’s second most populous nation can only be secured by institutions.