Background
Reports from the Horn of Africa suggest that Ethiopia and Eritrea are preparing for war. Both sides are fortifying their border positions, mobilizing troops, and escalating their verbal attacks. Eritrea is also allegedly stirring factionalism in Ethiopia, particularly in Tigray and Amhara, to destabilize the country from within.
A war would be disastrous for both countries. It would also damage their neighbors and make it nearly impossible for the Trump administration to achieve anything useful in this important region. Senate Foreign Relations Committee Chairman Jim Risch (R-ID) and 25 diplomatic delegations to Ethiopia have urged de-escalation. With tragedy looming, Congress and the Trump administration should mount a sustained diplomatic campaign to communicate to both sides that war is not an option.
The Ethiopia-Eritrea relationship has remained tense since Eritrea achieved independence in 1991. The success of Eritrea’s long struggle cut off Ethiopia’s access to the ocean, forcing Addis Ababa to depend on the port of Djibouti for nearly all imports and exports. This has long troubled Ethiopian leaders, and the country’s current prime minister, Abiy Ahmed, has publicly expressed his displeasure at Ethiopia’s lack of a navy.
From 1991 to 2018, the Ethiopian political party from Tigray, a state that borders Eritrea (see map 1), dominated the government in Addis Ababa. Amid this party’s rule, from 1998 to 2000, Ethiopia and Eritrea fought a costly border war, deepening the antagonism between the two countries—especially between Tigray and Eritrea.
Map 1. The Horn of Africa and Broader Region
Source: Author.
Tigrayan dominance ended in 2018 with the rise of Prime Minister Abiy Ahmed, who consolidated power in part by marginalizing the Tigrayan elite who once ruled Ethiopia. Abiy and Eritrean President Isaias Afwerki’s mutual disdain for the Tigrayans laid the groundwork for an unprecedented reconciliation between the two countries. The two continued to work together during the civil war that erupted between Tigray and the Ethiopian government in 2020.
But since that war ended in 2022, the Ethiopia-Eritrea relationship has deteriorated. Asmara was not involved in negotiating the Pretoria Agreement, which ended the war, and Ethiopian troops remain in Tigray in violation of the agreement. Additionally, fighting between Ethiopian federal troops and forces from the state of Ahmara—which Eritrea supported during the war against Tigray—broke out in 2023 and continues to this day.
Tigrayan elites have fractured. Some pushed to maintain the Pretoria Agreement, thereby aligning with Addis Ababa. Others saw Abiy and the government in Addis as their preeminent foe and aligned with their historic enemy, Eritrea.
The Abiy Era
Prime Minister Abiy has disquieted the region with public announcements that Ethiopia—Africa’s second-most populous country—requires access to the sea, arguing that the country’s landlocked status prevents it from “holding the place it ought to have.” His insistence on sea access appears to be driven more by a desire to secure a naval base and bolster Ethiopia’s geopolitical stature than a desire to address the country’s economic overreliance on Djibouti’s port.
Abiy began expressing his belief that Ethiopia requires a strong navy soon after he became prime minister. He made a deal with Somaliland’s leaders for a 19 percent stake in the autonomous region’s large and modern Berbera port, which would have helped Ethiopia diversify from Djibouti. But Ethiopia never fulfilled its obligations for implementing the agreement. Abiy subsequently negotiated a memorandum of understanding with Somaliland that would have given Ethiopia a naval base there. This time, international pressure, including from the United States, dissuaded Addis from following through, precluding what was perhaps the least disruptive way for Abiy to gain a base.
Now Abiy seems to have his sights set on the Eritrean port of Assab. Ethiopia has massive numerical superiority, and the Assab port is only about 50 miles from Ethiopia’s border. So Abiy is likely confident that an invasion would succeed. He may also expect support from the United Arab Emirates, Iran, and Türkiye, whose weapons helped save his government during the civil war with Tigray. An invasion through Tigray would be by far the easiest path for Ethiopia to seize Assab, which accounts for the two countries’ high-stakes struggle for influence in the state.
Geopolitical Implications of a Conflict
The results of such a war would be horrific. Even if Ethiopia quickly overruns Asmara’s conventional defenses, Eritreans would likely fight on as a guerilla insurgency—as they did for much of their 30-year independence struggle, which is now part of Eritrea’s national mythos. And Ethiopia’s numerical advantage did not prove decisive in Eritrea’s liberation struggle or the 1998 border war, during which the front lines moved only slightly despite tens of thousands of deaths on both sides.
Additionally, a new Ethiopia-Eritrea war would almost immediately become a proxy confrontation. Next door in Sudan, the Rapid Support Forces, which are backed by the UAE, are battling the Sudanese Armed Forces, which are backed by Egypt, Russia, and Iran. Egypt is especially likely to support the Eritreans given its long and bitter dispute with Ethiopia over the Grand Renaissance Dam on the Nile River. Egyptian commandos are also due in Somalia soon, ostensibly to fight the al-Shabaab terrorist organization there. These commandos could potentially open a second front against Ethiopia from Somalia.
The Horn of Africa, where this would unfold, is one of the world’s most volatile and strategic regions. It dominates vital shipping lanes through the Gulf of Aden and Red Sea, which connect Asia and Europe. The Red Sea also has one of the world’s highest concentrations of submarine cables. Eritrea, Djibouti, and Somaliland share maritime borders with vital Middle Eastern nations including Yemen, where the Trump administration is fighting an escalating conflict with the Iran-backed Houthi terrorist organization. The Horn also has thousands of miles of Indian Ocean coastline. Finally, Djibouti hosts Chinese, American, and other military bases and is one of the continent’s most important ports.
US Responses
If the Trump administration wishes to protect US interests in Africa, it will need to maintain relative stability in the Horn. An Ethiopia-Eritrea war could raise costs in the US by making the Red Sea even more inhospitable to shipping, thereby raising global oil prices. It might also give Iran openings in the region to expand its influence. The conflict’s shockwaves would quickly reach Djibouti and Somaliland, which would complicate US counterterrorism efforts in the Middle East and Africa. War would also likely drive massive population displacement, sending thousands of refugees into the Middle East and Europe. Finally, an Eritrea-Ethiopia war would imperil thousands of American citizens and significant US investments in the region.
On any given day, either Ethiopia or Eritrea could spark a live conflict—intentionally or otherwise. Such a conflict would devastate the region and create a significant obstacle to any plans the Trump administration may have for East Africa. A rapid and serious diplomatic push would be a small investment that could reap big dividends for the US and the region. But the clock is ticking.