Ethiopia PM Abiy Ahmed eyes Red Sea port, inflaming tensions
Ethiopia is abuzz with rumours of a new war - which would be Prime Minister Abiy Ahmed's fourth in five years.
As well as importing weapons and mobilising his army, Mr Abiy - who was awarded the Nobel Peace Prize in 2019 for his rapprochement with Eritrea - has been saying that access to the sea is an existential question.
Ethiopia's most obvious target is the Eritrean Red Sea port of Assab, which was part of Ethiopia until Eritrean independence more than 30 years ago.
Since the 1998 Ethiopian-Eritrean war and the closure of the border between the two countries, the Assab docks have been rusting away, while Ethiopia's trade has been channelled through neighbouring Djibouti.
The logistics and economics of Djibouti are perfectly workable, but it is not Ethiopian territory.
Many Ethiopians - and their neighbours - read between the lines and think the prime minister is threatening to use force.
But Mr Abiy publicly denies that he intends to invade Eritrea, telling soldiers recently on armed forces day: "Ethiopia has never invaded any country and will not do so in the future."
He has also called for dialogue via an emergency summit of the Inter-Governmental Authority on Development (Igad), a bloc of eight north-east African states.
Yet Ethiopia's aggressive posture and new arms race have consequences.
In July, Mr Abiy publicly raised the question of Ethiopia's access to the sea.
He made the point that Ethiopia is the world's most-populous landlocked country - it has 125 million people - and that access to the sea was a top priority for Ethiopian emperors, notably Haile Selassie who ruled from 1930 until 1974.
Quoting a famous 19th Century general, Ras Alula, Mr Abiy said that the Red Sea was Ethiopia's natural boundary.
He reportedly told a meeting of businessmen that "we want to get a port by peaceful means. But if that fails we will use force".
Some saw this as a gambit to win political support at home.
It appealed to an influential elite from the Amhara ethnic group who advocate for a greater Ethiopia.
Mr Abiy alienated this group when he made peace with the Tigray People's Liberation Front (TPLF) in northern Ethiopia a year ago, following a bloody civil war.
He further antagonised them by launching a military operation in April to disarm Amhara militia, who sided with him in the conflict in the Tigray region.
Many Ethiopians also believe, falsely, that international law entitles a large country to a seaport.
Another interpretation is that Mr Abiy is obsessed with his legacy, and sees acquiring a port, by force if it cannot be done by negotiation, as his contribution to Ethiopia's greatness.
For decades, Ethiopia's foreign policy was predictable. It wanted to stabilise the Horn of Africa under its own leadership.
Part of this was partnering with the United Nations and African Union on peace efforts in Sudan and Somalia. Ethiopia became Africa's biggest contributor to UN and African Union peacekeeping missions.
Another part was ambitious cross-border infrastructure projects, including transport corridors and power lines.
The Grand Ethiopian Renaissance Dam on the Nile was designed to generate enough electricity that it could export to neighbouring countries. The idea was to bind the Horn of Africa together as a single economic bloc.
Today, Mr Abiy has gained a reputation for unpredictability. That's the case for both domestic and foreign affairs.
In a remarkable reversal, Eritrea, once widely shunned for destabilising the Horn of Africa, is positioning itself as the responsible, status quo power.
In response to Mr Abiy, its statements have been terse and acerbic, pointedly refusing to join the "discourses" of its former ally on a matter that had "perplexed all concerned observers".
Ethiopia's other neighbours have been rattled too, and Djibouti, the self-declared Republic of Somaliland, Somalia and Kenya are joining Eritrea in an informal bloc to contain Ethiopia - issuing statements echoing one another's concerns.
Middle Eastern actors face dilemmas. The United Arab Emirates (UAE) is Mr Abiy's principal patron - most conspicuously, it is financing his lavish palace, as well as providing drones.
Emirati aircraft have been observed unloading supplies in Ethiopian airbases in recent days.
Abu Dhabi also supports Sudan's paramilitary Rapid Support Forces (RSF) group led by General Mohamed Hamdan Dagolo, known as "Hemeti", who controls much of Sudan including most of its capital, Khartoum, and may soon be able to form a government.
For the UAE, Mr Abiy's adventurism is both an opportunity and a risk: Ethiopia could become an important Red Sea power - and an Emirati client state; or a new war in the Horn could jeopardise their gains in Sudan.
Saudi Arabia, on the other hand, is sponsoring ceasefire talks in Sudan jointly with the US and is reportedly disturbed by how Mr Abiy's Ethiopia is acting.
If Mr Abiy overreaches, Saudi Arabia may feel obliged to overcome its wariness over the Eritrean President Isaias Afewerki, and support him.
If he is serious about a new war, Mr Abiy faces two major challenges. One is who will fight.
The Ethiopian army has been depleted by the last three wars. The first was against the Oromo Liberation Army, and is still unfinished.
The second war, against the Tigray People's Liberation Front (TPLF), was fought in alliance with Eritrea, and ended with a cessation of hostilities a year ago. The Ethiopian army lost, by its own calculation, between 260,000 and 520,000 soldiers killed or missing in action, plus 374,000 wounded.
The third war, against Amhara militia, began in April and is bogging down a large proportion of the army in what increasingly looks like a quagmire - with reports that Eritrea is arming the Amhara militia, known as Fano.
If Addis Ababa is to go to war, it will probably need the active involvement of Tigray, strategically positioned adjoining Eritrea.
But Tigray's economy and services were destroyed in the two-year war that ended last year, and its people are exhausted.
Few have an appetite for new fighting. But there is deep and widespread anger at the atrocities committed by the Eritrean army.
Moreover, if the federal army were to start a war with Eritrea, Tigray would certainly be dragged in.
Some Tigrayans, fearing that a new war is inevitable, argue that Tigray should set out its conditions first, such as a return of western Tigray - seized by the neighbouring Amhara region three years ago - and control over some national military assets such as aircraft.
A second challenge is paying for the war. The Ethiopian economy is in a tailspin, and desperately needs a bailout from western donors along with the International Monetary Fund (IMF) and World Bank.
Mr Abiy may hope that the UAE will compensate for any lost funds, but while UAE President Mohamed bin Zayed al-Nahyan may provide cash-in-hand for the prime minister, his money cannot compensate for the massive economic losses that a war would entail.
Whether or not Ethiopia actually launches an invasion, Mr Abiy has made the war thinkable.
Beating the drums of war creates a dangerous atmosphere. The region's arms race is quickening. Ethiopia is buying more weapons. Eritrea and Djibouti will likely follow suit. Tigray's proposed demobilisation is frozen. The conflicts in Somalia may be exacerbated. Eritrea could pour arms to the Amhara militia to intensify that war.
There is a danger that any small incident could get out of hand.
The last thing that the Horn of Africa needs is a new war. But the risks are now alarmingly high.
-bbc