Yemen War
ACLED Update — 2026-05-20
- [2025-05-20] Battles — Armed clash | Military Forces of Yemen (2022-2026) Presidential Leadership Council - STC Support and Reinforcement Brigades vs Military Forces of Yemen (2022-2026) Presidential Leadership Council - STC Support and Reinforcement Brigades | Zinjibar
- On 20 May 2025, officers from the 6th Brigade of the STC Support and Reinforcement Brigades exchanged fire with each oth (Twitter)
- [2025-05-20] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Military Forces of Yemen (2022-2026) Presidential Leadership Council - STC Saiqa Brigades | Habil Hanash
- On 20 May 2025, Houthi forces clashed with the STC 13th Saiqa Brigade, Southern Resistance forces, Security Belt forces, (Undisclosed Source)
- [2025-05-13] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Southern Resistance | Aqabat Thirah
- On 13 May 2025, Houthi forces fired mortars and drones at Southern Resistance forces on the Thirah front (coded to Aqaba (Aden al Ghad; Dera Al Ganoob; Khabar News Agency (Yemen); Undisclosed Source)
- [2025-05-13] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Military Forces of Yemen (2022-2026) Presidential Leadership Council - STC Support and Reinforcement Brigades | Jabal Humalah
- On 13 May 2025, Houthi forces clashed with STC forces of the 5th Support and Reinforcement Brigade. 6th STC Hazm brigade (Undisclosed Source)
- [2025-05-13] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Military Forces of Yemen (2022-2026) Presidential Leadership Council - STC | Shurayjah
- On 13 May 2025, Houthi forces clashed with the STC 6th Infantry Brigade (coded as STC generic forces) and STC 2nd, 3rd a (Undisclosed Source)
- [2025-05-13] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Military Forces of Yemen (2022-2026) Presidential Leadership Council - 30th Armored Brigade | Jabal Murays
- On 13 May 2025, Houthi forces clashed with the forces of the IRG 30th Armored Brigade, STC Security Belt Forces, 5th Spe (Undisclosed Source)
- [2025-05-20] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Military Forces of Yemen (2022-2026) Presidential Leadership Council | Al Fakhir
- On 20 May 2025, Houthi forces clashed with IRG 30th and 33rd Armored Brigades, STC 1st Saiqa Brigade, 2nd Commando Briga (Undisclosed Source)
- [2025-05-20] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Military Forces of Yemen (2022-2026) Presidential Leadership Council - STC Support and Reinforcement Brigades | Al Masharih
- On 20 May 2025, Houthi forces clashed with STC 7th Support and Reinforcement Brigade, 3rd and 5th Southern Resistance Br (Undisclosed Source)
- [2025-05-20] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Police Forces of Yemen (2022-2026) Presidential Leadership Council - STC Security Belt Forces | Rayshan
- On 20 May 2025, Houthi forces clashed with the STC Security Belt forces and the 3rd Infantry Brigade (coded as generic S (Undisclosed Source) BLUF
The Yemen War (September 2014–present) began as a domestic power struggle between the Ansar Allah movement (Houthis) and the internationally recognized government, escalated into a regional proxy war when the Saudi-led coalition intervened in March 2015, and has entered a third phase since October 2023 defined by the Houthi Red Sea interdiction campaign against international shipping — transforming Yemen from a contained civil war into a node in the regional confrontation between the Iran-backed “Axis of Resistance” and the US-Israel-Gulf alignment. (Fact, High.)
The conflict has produced the world’s largest humanitarian catastrophe: 21 million people food insecure, over 4 million internally displaced, and infrastructure systematically destroyed across a decade of air campaigns, ground offensives, and blockades. The 2022 UN-brokered truce partially paused fighting along the principal front lines but collapsed in its formal framework; no sustainable ceasefire architecture currently exists. (Fact, High; OCHA / UN Panel of Experts.)
Assessment (High). Current strategic trajectory: Ansar Allah has used the Gaza War to reframe the Yemen conflict as anti-imperialist resistance, gaining legitimacy in the Arab street while US-UK strikes (Operation Prosperity Guardian, from January 2024) have failed to degrade the Houthi maritime capability. Saudi Arabia’s willingness to pursue a negotiated exit is structurally constrained by Houthi refusal to separate the Red Sea campaign from a Yemen settlement — leaving Riyadh negotiating from a position of weakness and Western maritime freedom-of-action contested for the first time since the tanker wars of the 1980s.
Strategic Overview
The Yemen War encompasses the civil conflict that began with the Houthi (Ansar Allah) seizure of Sana’a in September 2014 and escalated into a regional proxy war following the Saudi-led coalition intervention in March 2015. As of 2025, the conflict has entered a new phase defined by the Houthi campaign of attacks on Red Sea commercial shipping and US/UK naval assets in response to the Gaza War (from October 2023), transforming Yemen into a node in the wider regional confrontation between Iran-backed actors and the US-Israel-Gulf alignment.
Key Actors
- Ansar Allah (Houthis) — de facto governing authority in northwest Yemen including Sana’a; Iran-supplied ballistic missiles, drones, and anti-ship weapons; active Red Sea interdiction campaign since 2023.
- Presidential Leadership Council (PLC) — internationally recognized government; Saudi-backed; fragmented internal coalition.
- Southern Transitional Council (STC) — UAE-backed secessionist council; controls Aden and southern governorates.
- Saudi Arabia — coalition lead; air campaign since 2015; diplomatic interest in ceasefire since 2023 Riyadh-Tehran normalization.
- UAE — withdrew ground forces 2019; maintains STC patronage and Socotra presence.
- Iran — arms supplier, strategic enabler for Houthis; denied direct operational control.
- United States / United Kingdom — Operation Prosperity Guardian and direct strikes on Houthi targets from January 2024.
Humanitarian Situation
- 21 million food insecure (UN OCHA, 2024) — the largest food crisis in the world by absolute numbers; roughly two-thirds of Yemen’s population.
- 4.5 million internally displaced persons (IDPs) — IOM/UNHCR; many in protracted multi-year displacement across Ma’rib, Hodeidah, and Hadhramaut governorates.
- 150,000+ killed since 2015 (direct and indirect deaths; ACLED / UN composite estimate). Indirect mortality (disease, malnutrition, denial-of-care) is the larger share — the structural signature of a siege economy.
- Hodeidah port — point of entry for ~70% of Yemen’s food imports — repeatedly targeted across the campaign; current status: operational but degraded, with throughput well below pre-war baseline.
- Saudi blockade periods (2017–2022) materially worsened humanitarian access; the Stockholm Agreement (December 2018) partially opened Hodeidah but did not resolve the structural import bottleneck.
- Cholera, malnutrition, and health-system collapse documented continuously by WHO and ICRC — Yemen recorded one of the largest cholera outbreaks of the 21st century (2017–present, recurring waves). (Fact, High.)
Assessment (High). Yemen’s humanitarian crisis is not a byproduct of the war but a structural feature of how the war is fought: control over Hodeidah, customs revenue, and import licensing is itself the prize. Any durable settlement must resolve the war economy — not merely the front lines.
Red Sea Campaign — Strategic Dimension
| Date | Event | Strategic significance |
|---|---|---|
| 2023-10-19 | First Houthi attack on Israel-linked shipping | Opens maritime front; cites Gaza War solidarity; reframes Yemen as Axis of Resistance node |
| 2023-11 | Capture of Galaxy Leader (Israeli-linked cargo vessel) | Demonstration of interdiction capability; high-visibility hostage-vessel propaganda value |
| 2024-01-12 | US-UK strikes on Houthi targets in Yemen (CENTCOM / Operation Prosperity Guardian) | First direct kinetic action against Houthi military infrastructure; coalition-of-the-willing maritime escort |
| 2024-Q1–Q2 | 100+ attacks on vessels; estimated $10B+ damage to shipping rerouting | Red Sea traffic down ~60%; Cape of Good Hope rerouting adds ~10 days transit; insurance premia spike |
| 2025-05 | US-Houthi ceasefire announced (does not include Israel) | Partial US disengagement from maritime campaign; bifurcates the deterrence problem |
Assessment (High). The Red Sea campaign demonstrates that a non-state actor with precision-guided ballistic missiles, anti-ship cruise missiles, and one-way attack drones can impose strategic-level costs on global maritime commerce. The campaign has not been degraded by US/UK strikes despite months of kinetic action — confirming the distributed, dispersed, and hardened nature of the Houthi missile/drone infrastructure (mobile launchers, cave storage, redundant command). This is the first sustained successful denial of a global maritime chokepoint by a non-state actor since the Tanker War (1984–1988), and the operational signature it establishes is directly transferable.
Iran-US War Context — May 2026
Update: 2026-05-15. Source: mcp__fetch from Al Jazeera primary URLs; Tavily/Exa/WebSearch non-operational.
The Yemen conflict entered a structurally distinct phase on 28 February 2026 when Operation Lion’s Roar (US-Israeli strikes on Iran) began, triggering the Houthi dual-posture problem: Ansar Allah is simultaneously (1) a formal US-Houthi ceasefire party (announced ~2026-05 window; Red Sea maritime campaign nominally suspended) and (2) a declared member of the Axis of Resistance coalition with Iran, which remains in a post-ceasefire but unresolved confrontation with the US.
Key developments (2026-05 window):
-
US-Houthi ceasefire — announced without including Israel; Ansar Allah retains the formal right to target Israeli-linked shipping and stated it would resume maritime operations if Israel continued operations in Gaza. This bifurcates the Red Sea deterrence problem: US commercial shipping may be de-escalated; Israeli-linked shipping remains contested. (Fact, Medium — Al Jazeera; ceasefire terms not publicly released in full.)
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Iran-US talks — “TOTALLY UNACCEPTABLE” — On 2026-05-11, the Houthi political bureau characterized ongoing US-Iran nuclear/normalization talks using the phrase “totally unacceptable” in a public statement. This signals Ansar Allah’s concern that a US-Iran bilateral deal could sideline or constrain their posture, absent Houthi inclusion in any regional framework. (Fact, Medium — Al Jazeera.)
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Cash shortage in Houthi-controlled territories — Reporting in the 2026-05 window documents a cash liquidity crisis in Houthi-controlled areas, linked to Iran’s reduced financial transfers under ceasefire-period economic pressure. If persistent, this constrains Ansar Allah’s civil-governance capacity and social services network. (Assessment, Medium.)
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Recalibration risk — Bab al-Mandeb reactivation — Elevated risk of Houthi maritime campaign reactivation against Israeli-linked or Gulf-linked shipping if: (a) Iran-US normalization talks proceed without Houthi inclusion, (b) Gaza operations continue at elevated tempo (+35% since Iran ceasefire per Al Jazeera 2026-05-13), or (c) the US-Houthi ceasefire breaks on technical grounds. (Assessment, Medium-High.)
Strategic significance: The Iran-US ceasefire (2026-04-08) has bifurcated the Axis of Resistance architecture from a unified deterrence posture to a disaggregated posture. This disaggregation may reduce Western maritime risk in the short term but increases the risk of selective reactivation by individual proxy actors calibrated to their own political constraints.
Timeline Anchors
| Date | Event |
|---|---|
| 2014-09-21 | Houthis seize Sana’a |
| 2015-03-26 | Saudi-led coalition intervention begins |
| 2018-12-13 | Stockholm Agreement (Hodeidah ceasefire) |
| 2022-04-02 | UN-brokered nationwide truce |
| 2023-10-19 | Houthis begin Red Sea shipping attacks citing Gaza solidarity |
| 2024-01-12 | US-UK first direct strikes on Houthi targets in Yemen |
| 2026-02-28 | Operation Lion’s Roar begins (US-Israeli strikes on Iran); Axis of Resistance enters full-activation phase |
| 2026-04-08 | Iran-US ceasefire; US-Houthi maritime ceasefire announced (Israel not included) |
| 2026-05-11 | Houthi political bureau characterizes US-Iran normalization talks as “totally unacceptable” |
Strategic Implications
1. The Houthi transformation — from domestic insurgency to regional deterrence instrument. Ansar Allah has completed an operational evolution unparalleled among Iran-aligned non-state actors: from a Zaydi revivalist movement in Sa’ada (1990s) to the de facto sovereign of northwest Yemen and now to Iran’s most effective deterrence instrument against US/Israel freedom of action in the Red Sea. The strategic logic: the Red Sea campaign functions as the maritime extension of the Axis of Resistance deterrence architecture, applying costs to Western economic interests without requiring direct confrontation with US forces and without exposing Iran to attribution. This is hybrid deterrence-by-denial executed at scale. (Assessment, High.)
2. The Saudi dilemma. Riyadh needs a Yemen exit — the war has imposed direct costs (cross-border missile/drone strikes on Aramco facilities, Riyadh, Abu Dhabi), reputational costs (Khashoggi, civilian casualty record), and opportunity costs (Vision 2030 capital signaling). But Saudi Arabia cannot accept permanent Houthi control of the Hodeidah corridor and the Sa’ada–Sana’a axis without effectively conceding a hostile, Iran-aligned northern frontier. The 2023 Saudi-Iran normalization (Beijing-brokered) created political space for a settlement, but Ansar Allah’s refusal to separate the Red Sea campaign from Yemen status negotiations leaves Saudi Arabia negotiating from weakness — without the leverage to compel terms and without the willingness to re-escalate. (Assessment, High.)
3. The precedent — hybrid maritime warfare doctrine. If Houthi Red Sea interdiction succeeded in imposing strategic costs on global shipping without being defeated, it establishes a transferable doctrine for hybrid maritime warfare by Iran-backed (and other) non-state actors. The implications extend directly to the Strait of Hormuz, the Persian Gulf, the Bab el-Mandeb, and any chokepoint within range of cheap precision missiles and drones. This restructures Western deterrence calculations: maritime supremacy can no longer be assumed in any littoral against an actor willing to absorb retaliation and equipped with $10K–$100K weapons targeting $100M+ platforms — a cost-exchange ratio that favors the attacker indefinitely. (Assessment, High.) See Proxy Warfare and Cost-Exchange Asymmetry.
Cross-References
- Ansar Allah
- Saudi Arabia
- Iran
- United Arab Emirates
- Yemen-SaudiUAE-Proxy-Cold-War
- Yemen-ACLED-Events
- Red Sea — Maritime Security
- Proxy Warfare
ACLED Coverage
ACLED country code: Yemen — events appended automatically by Automation/acled/acled_ingest.py.
Related Notes
- Yemen-ACLED-Events
- Yemen-SaudiUAE-Proxy-Cold-War
- Ansar Allah
- Saudi Arabia
- Red Sea — Maritime Security
Sources
- UN Office for the Coordination of Humanitarian Affairs (OCHA) — Yemen Humanitarian Response Plan (2024) — Fact, High (primary, authoritative).
- ACLED — Armed Conflict Location & Event Data, Yemen dataset — Fact, High (primary dataset).
- CENTCOM — Operation Prosperity Guardian official statements and press releases (2024–) — Fact, High (primary, US military).
- Council on Foreign Relations — Yemen Conflict Tracker — Assessment, Medium (think-tank synthesis).
- Chatham House — Yemen studies and policy briefs (2022–2025), including Peter Salisbury’s analytical work — Assessment, High.
- UN Panel of Experts on Yemen — arms embargo monitoring reports (annual to UN Security Council) — Fact, High (primary, authoritative).
- WHO / ICRC — Yemen health-system and cholera outbreak reporting — Fact, High.
- IOM / UNHCR — IDP and displacement tracking — Fact, High.
ACLED Update — 2026-05-15
- [2025-05-08] Battles — Armed clash | Unidentified Armed Group (Yemen) vs Military Forces of Yemen (2022-2026) Presidential Leadership Council - STC Support and Reinforcement Brigades | Aden - Jawlat Suzuki | 1 fatalities
- On 8 May 2025, unidentified armed men shot, looted, and killed the officer of the 1st STC Support and Reinforcement Brig (Twitter)
- [2025-05-15] Battles — Armed clash | Hammam Tribal Militia (Yemen) vs Al Mabasi Tribal Militia (Yemen) | Awshah
- On 15 May 2025, at noon, armed clashes erupted between Hammam and Al Mabasi tribes in Awshah (Nisab, Shabwah) resulting (Twitter; Undisclosed Source)
- [2025-05-08] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs West Coast Joint Forces | Al Jarbah
- On 8 May 2025, Houthi forces exchanged limited mortar and artillery fire with the pro-IRG forces (coded as WCJF) in Nakh (Undisclosed Source)
- [2025-05-08] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs West Coast Joint Forces | Nakhlah
- On 8 May 2025, Houthi forces exchanged limited mortar and artillery fire with the pro-IRG forces (coded as WCJF) in Nakh (Undisclosed Source)
- [2025-05-08] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs West Coast Joint Forces | Al Bughayl
- On 8 May 2025, Houthi forces exchanged limited mortar and artillery fire with the pro-IRG forces (coded as WCJF) in Al B (Undisclosed Source)
- [2025-05-08] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Military Forces of Yemen (2022-2026) Presidential Leadership Council - STC | Wadi as Sahi
- On 8 May 2025, Houthi forces clashed with the STC 6th Infantry Brigade and STC 2nd Hazm Brigade in Shifan Al Sahi front (Undisclosed Source)
- [2025-05-08] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Military Forces of Yemen (2022-2026) Presidential Leadership Council | Bab Ghaliq
- On 8 May 2025, Houthi forces clashed with the IRG 30th and 33rd Armored Brigades, 1st and 4th Southern Resistance Brigad (Undisclosed Source)
- [2025-05-15] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs West Coast Joint Forces | Al Muharraq
- On 15 May 2025, Houthi forces exchanged limited mortar and artillery fire with the pro-IRG forces (coded as WCJF) in Nak (Undisclosed Source)
- [2025-05-15] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs West Coast Joint Forces | Ar Rawn
- On 15 May 2025, Houthi forces exchanged limited mortar and artillery fire with the pro-IRG forces (coded as WCJF) in Ar (Undisclosed Source)
- [2025-05-15] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs West Coast Joint Forces | Al Jarbah
- On 15 May 2025, Houthi forces exchanged limited mortar and artillery fire with the pro-IRG forces (coded as WCJF) in Nak (Undisclosed Source)
- [2025-05-15] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs West Coast Joint Forces | Nakhlah
- On 15 May 2025, Houthi forces exchanged limited mortar and artillery fire with the pro-IRG forces (coded as WCJF) in Nak (Undisclosed Source)
- [2025-05-15] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Police Forces of Yemen (2022-2026) Presidential Leadership Council - STC Security Belt Forces | Rayshan | 4 fatalities
- On 15 May 2025, Houthi forces clashed with the STC Security Belt forces and the 3rd Infantry Brigade (coded as generic S (Undisclosed Source)
- [2025-05-15] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs Military Forces of Yemen (2022-2026) Presidential Leadership Council - STC Support and Reinforcement Brigades | Jabal Humalah
- On 15 May 2025, Houthi forces clashed with STC forces of the 5th Support and Reinforcement Brigade, the 13th Saiqa Briga (Undisclosed Source)
- [2025-05-08] Battles — Armed clash | Military Forces of Yemen (2017-) Houthi vs West Coast Joint Forces | Al Muharraq
- On 8 May 2025, Houthi forces exchanged limited mortar and artillery fire with the pro-IRG forces (coded as WCJF) in Nakh (Undisclosed Source)