Washington is watching a dangerous pattern re-emerge in the Horn of Africa, one it has seen before and failed to stop. Ethiopia and Eritrea are again moving toward confrontation, and Addis Ababa has repeatedly warned Washington and other international partners that Eritrea’s military posture, presence on Ethiopian territory, and support for armed actors inside Ethiopia are creating a new casus belli. The parallel with 1997–98 is striking.
Ethiopia then issued repeated warnings as Eritrea escalated a campaign of subversion and military coercion that culminated in the invasion of Ethiopian-administered territory in May 1998. However, the international response, including Washington’s, remained centered on mediation after the facts on the ground had already begun to change. Addis Ababa has been warning Washington again for at least two years, and the strategic indicators preceding the 1998 war are once more becoming visible. If Washington treats these warnings as merely another round of Horn of Africa brinkmanship, it risks allowing a preventable crisis to acquire the momentum of a war.
If Washington treats these warnings as merely another round of Horn of Africa brinkmanship, it risks allowing a preventable crisis to acquire the momentum of a war.
The lesson of 1998 is not that post-war diplomacy was futile; it is that pre-war diplomacy conducted without credible consequences can give an increasingly assertive state room to test the limits of international tolerance. During the Tigray war, and with increasing urgency following the November 2022 Pretoria Agreement, Ethiopia repeatedly warned that Eritrean forces had not fully withdrawn from Ethiopian territory and that Asmara was cultivating relationships with armed actors hostile to the Ethiopian state.
The broader pattern is unmistakable: Asmara has employed this highly militarized conception of regional security and projected force beyond its borders with striking regularity. It became involved in Sudan, reportedly supporting the Muslim Brotherhood-aligned Sudanese Armed Forces, which Washington sanctioned only months ago. Its historical support for Al-Shabaab, which contributed to more than two decades of U.S. and allied sanctions and international isolation, further illustrates the pattern.
This record warrants scrutiny. Eritrea’s repeated intervention in the wars of its immediate and neighbors and beyond, including Yemen, demonstrates a willingness to project military power across the region, especially during periods of extreme political and military vulnerability in neighboring countries.
By February 2026, Ethiopia’s warnings had become formal diplomatic charges. Foreign Minister Gedion Timothewos accused Eritrea of “military aggression,” alleged that Eritrean forces were occupying Ethiopian territory, demanded their withdrawal, and accused Asmara of materially supporting armed groups inside Ethiopia deliberately manipulating the latter’s internal security environment. Asmara’s public posture toward these allegations failed to convey the restraint one would expect from a state seeking to dispel fears of regional escalation; rather, it projected defiance and bravado about its capacity to shape Ethiopia’s internal strategic environment.
Addis Ababa has also repeatedly raised these concerns directly with Washington, including in formal communications to Secretary of State Marco Rubio. Washington is not approaching this crisis in the dark. It has had more than two years of warnings, diplomatic documentation, and requests for engagement—an extraordinary opportunity for preventive action that was not effectively converted into deterrence before the 1998 war.
Eritrea’s conduct against Ethiopia must be assessed not as an isolated bilateral dispute, but as part of a broader regional security problem with direct implications for U.S. interests.
For Washington, the stakes are now higher. A renewed Ethiopia-Eritrea conflict would not unfold in the strategic environment of 1998. It would intersect with the wars in Sudan and the Middle East, the security of the Red Sea, the competition among regional and global powers, and the growing involvement of external actors across the Horn of Africa. Eritrea’s conduct against Ethiopia must be assessed not as an isolated bilateral dispute, but as part of a broader regional security problem with direct implications for U.S. interests. A new Ethiopia-Eritrea war could rapidly acquire a regional dimension, drawing in actors beyond the two states and placing additional pressure on an already vulnerable strategic corridor.
The consequences for Washington would extend directly to Red Sea security, counterterrorism, and humanitarian stability. With the Strait of Hormuz closed and the wider Middle East already experiencing a profound security crisis, Washington can ill afford to watch another major strategic crisis develop anywhere near the Bab el-Mandeb Strait—which would create strategic vulnerability by compounding the pressure already facing U.S. forces, partners, and global commerce across the region.
As in 1998, Ethiopia is warning again, and Washington has enough information to understand the danger and pursue preventive deterrence. What is now required is the strategic foresight to act on it before deterrence gives way to war.
