The Houthis' Attack on Four Saudi Cities and the Reignited Yemeni Civil War: Reshaping the Gulf Security Architecture and South Korea's Response

Executive Summary

The Houthi rebels' simultaneous strikes on four Saudi cities are not a localized resurgence of Yemen's civil war, but a consequence of the Israel-Iran war that began in February 2026, which has reshaped the Gulf security landscape. Iran is using the Houthis as a low-cost proxy lever to maintain its negotiating power over the Strait of Hormuz, and as long as this structure remains, the risk of renewed attacks on Saudi Arabia will persist. The Mecca Defense Pact, a symbolic signal lacking an automatic intervention clause, failed to deter this attack, leaving Saudi Arabia to effectively respond alone. The baseline scenario for the next six months is continued localized conflict and entrenched risks to Red Sea shipping routes. If the dual chokepoints of Hormuz and Bab el-Mandeb become a reality, South Korea's energy import lines and the safety of its nationals abroad could be simultaneously jeopardized. The South Korean government and companies should not rush to normalize shipping routes but should instead pursue a phased approach: institutionalizing rerouting via the Cape of Good Hope, diversifying procurement sources in eastern Saudi Arabia, and separately monitoring the phase of testing the Mecca Pact's effectiveness.

I. Issue Analysis

The Houthi Rebels' Attack on Four Saudi Cities and the Reignited Yemeni Civil War: An Issue Analysis

1. Background and Developments

The starting point of this crisis is not the Yemeni civil war itself. It is the result of the Israel-Iran war, which began in February 2026 and has shaken the entire Gulf security landscape [3][9]. The Houthis, who control most of Yemen's densely populated areas and the capital, Sanaa, are an Iranian proxy force [1][4]. As the war with Iran intensified, the Houthis resumed their attacks targeting Saudi Arabia.

The decisive turning point came in early July. Two Iranian aircraft landed in Houthi-controlled territory [2][11]. This triggered the largest-scale Saudi-Houthi engagement since the UN-brokered truce in 2022 [2][5]. The Sanaa Center recorded that fighting on the front lines intensified following clashes around Sanaa's airport [5].

In response, the Houthis declared a maritime blockade targeting Saudi Arabia. They claimed to have attacked three ships in the Red Sea [2][9]. They also targeted Saudi airports and oil infrastructure [2]. The Yemeni government forces struck the runway at Sanaa's airport, and Riyadh conducted airstrikes on Houthi military and communications facilities on the Hodeidah coast [2][9]. The UN Special Envoy for Yemen had warned that the risk of a return to full-scale war was higher than at any time since the April 2022 truce [5].

Separately from this dynamic, the internal landscape in Saudi Arabia also changed. In January 2026, forces of the Southern Transitional Council (STC), which had been supported by the UAE, were ousted from Hadhramaut and Al-Mahra by Saudi airstrikes and pressure from tribal forces [13]. STC leader Ayderus al-Zubaidi was reported to have gone into exile, and Emirati forces completely withdrew from Yemen [13]. In this process, Saudi Arabia absorbed the southern forces into its sphere of influence. This can be seen as a move by Saudi Arabia to secure its rear before a full-scale confrontation with the Houthis.

2. Current Situation

On Tuesday, September 8, the Houthis simultaneously struck four cities in southern Saudi Arabia with drones and missiles [1][4]. The Houthis targeted a Saudi air force base in Khamis Mushait and facilities of the state-owned oil company in nearby Abha [1]. At least 73 people were injured, including children [10]. Fires broke out at several oil facilities [7][10].

The Houthi side announced that it had launched an extensive operation deep into Saudi territory [1][4]. Reuters assessed this as a significant escalation in the six-month-long Middle East war [1]. Le Monde noted that the attack occurred immediately after deadly clashes in Iran, Lebanon, and Gaza, raising the stakes between U.S. allies and Iranian proxies [7].

The Chilean newspaper El Mercurio reported that over 300 people had died in recent clashes as the war reignited, and cited expert opinion that the Houthis are attempting to seize territory along the Bab el-Mandeb Strait [12]. The Swiss newspaper NZZ reported that Riyadh is threatening massive retaliation against the Houthis while Yemeni government forces are pressuring them on the ground [14]. NZZ pointed out that this attack is a test of the effectiveness of the newly signed 'Mecca Pact' [14].

Foreign Policy diagnosed that this situation risks adding a new front to the Iran conflict [15]. The Daily Maverick reported that the front is expanding, with the United States striking an Iranian oil tanker [18].

3. Key Actors and Interests

The Houthis (Ansar Allah)act as an Iranian proxy force, leveraging their de facto control within Yemen [3]. In the context of the Iran-Israel war, the Houthis' attacks on Saudi Arabia are less about their own cause and more about serving Iran's broader strategy of maintaining negotiating power over the Strait of Hormuz [3][6]. The Houthis are using their declaration of a maritime blockade and their attempt to seize control of the Bab el-Mandeb Strait to turn the Red Sea shipping route itself into a bargaining chip [9][12].

Saudi Arabiais forced to choose between defense and retaliation after the collapse of its four-year truce with the Houthis [14]. As its oil infrastructure has been directly hit, it is difficult for Riyadh to de-escalate its response. At the same time, having reshuffled its sphere of influence in Yemen by absorbing the southern STC forces, there is also an incentive to use this situation as an opportunity to oust the Houthis [13].

Iranis operating a low-cost lever through the Houthis to pressure Saudi Arabia without a direct trace of its involvement [3][6]. The landing of Iranian aircraft in Houthi territory is a symbolic event that demonstrates this proxy war structure [2][11]. Iran is pursuing a strategy of applying multi-front pressure on Saudi Arabia by maintaining its negotiating power in the Strait of Hormuz while simultaneously opening a front in the Red Sea.

Pakistanhas publicly stated that the Houthi attack could trigger the automatic intervention clause based on the Mecca Joint Defense Pact signed on August 7. Pakistani Defense Minister Khawaja Asif commented, "If there is an armed aggression where the Yemen situation spills over into Saudi Arabia, the Mecca Pact will definitely be invoked" [17]. This aligns with the Council on Foreign Relations (CFR) analysis that the pact has the character of a security guarantee comparable to a NATO-style automatic intervention clause [8]. The CFR assesses that this pact establishes a mutual security structure in which Saudi Arabia and Türkiye would defend Pakistan in a South Asian conflict, and in return, Saudi Arabia and Pakistan could side with Türkiye in a conflict between Israel and Türkiye [8].

Türkiyeis another pillar of the Mecca Pact and a potential party to intervention, linked to the situations in Syria and the Eastern Mediterranean [8]. However, an immediate response from Türkiye to this Houthi attack has not been confirmed.

United Statesis already involved in the conflict with Iran, having struck an Iranian oil tanker [18]. While Saudi Arabia is a long-standing U.S. ally, the emergence of the Mecca Pact itself is seen by some as symbolizing the end of the U.S.-led order in the Middle East, as the CFR has pointed out [8]. This is read as a signal that Saudi Arabia is building its own regional defense network outside the U.S. security umbrella.

4. Key Issues

First is the issue of the Mecca Pact's effectiveness. Although Pakistan has publicly suggested the possibility of its invocation [17], the text of the pact has not been released, and the specific conditions for triggering the automatic intervention clause are unclear [8]. Whether this attack actually leads to automatic intervention will be the first test of the pact's credibility [14].

Second is the stability of passage through the Bab el-Mandeb Strait. The Houthis' declaration of a maritime blockade and claims of attacking ships [2][9] cast doubt on the safety of the entire Red Sea shipping route. If this overlaps with tensions in the Strait of Hormuz, a situation where both chokepoints become unstable simultaneously cannot be ruled out.

Third is the deepening linkage between the Iran-Israel war and the Yemeni civil war. The fact that the Houthi attacks are not a separate issue but are operating as part of a multi-front conflict managed by Iran raises the possibility that the localized war in Yemen could become entrenched as a secondary front in the regional war [15][18].

Fourth is the level of Saudi Arabia's response. The future course of the Yemeni civil war and the entire Gulf region's security architecture will depend on whether Riyadh limits its response to threats of retaliation or shifts to a full-scale offensive against Houthi strongholds [14].

II. In-Depth Analysis

The Houthi Rebels' Attack on Four Saudi Cities and the Reignited Yemeni Civil War: An In-Depth Analysis

1. Analysis of Root Causes

To view this situation as a simple resurgence of Yemen's civil war is to misread the causal relationships. The root cause lies outside Yemen. The Israel-Iran war, which began in February 2026, has shaken the entire Gulf security landscape [3][6]. The decisive factor is that this war has prompted Iran to recalibrate its strategy of employing proxy forces.

Iran's calculation is to maintain direct negotiating leverage in the Strait of Hormuz while avoiding leaving a clear footprint of its intervention. An EAI analysis noted, "Iran is using the Houthis as a low-cost proxy lever to maintain its negotiating power over the Strait of Hormuz" [3]. The landing of two Iranian aircraft in Houthi-controlled territory in early July is physical evidence of this proxy war structure [2][11]. The fact that this single symbolic act—the arrival of aircraft—triggered the largest-scale Saudi-Houthi engagement since the 2022 truce shows that the Houthis' military actions are more responsive to Iran's external strategy than to Yemen's internal dynamics.

From the Houthis' perspective, this situation is a no-lose proposition. At a time when Iranian attention and support are focused due to the Israel-Iran war, resuming offensives against Saudi Arabia allows them to simultaneously enhance their own negotiating position within Yemen and their control over the Bab el-Mandeb Strait. El Mercurio reported expert opinion that the Houthis are aiming to seize territory along this strait [12]. Control of the strait provides the Houthis with leverage to capture the international community's attention and is a means of tangible pressure on Saudi Arabia and the West.

2. Structural Context

Security Structure: The Vacuum in the U.S.-Led Order

The most prominent feature of the security context of this incident is the absence of the United States. The CFR interpreted the signing of the Mecca Defense Pact itself as a signal of "the end of the U.S.-led order in the Middle East" [8]. The fact that Saudi Arabia signed a pact with Pakistan and Türkiye containing a clause similar to NATO's Article 5, rather than relying on U.S. extended deterrence, is evidence that Riyadh no longer takes Washington's security guarantees for granted.

However, the effectiveness of this emerging security structure has not yet been tested. EAI assessed that "the Mecca Defense Pact, a symbolic signal lacking an automatic intervention clause, failed to deter this attack, leaving Saudi Arabia effectively in a position to respond alone" [3]. Although Pakistani Defense Minister Khawaja Asif stated that "if the Yemen situation spills over into Saudi Arabia, the Mecca Pact will definitely be invoked" [17], this was a post-facto political statement and failed to function as a deterrent beforehand. NZZ described the attack as "a test of the effectiveness of the newly signed Mecca Pact" [14], which paradoxically confirms that the pact is an unfinished structure that has not yet been validated.

Economic Structure: The Vulnerability of a Dual Chokepoint

The Red Sea-Bab el-Mandeb route, along with the Strait of Hormuz, constitutes the two main gateways for Gulf energy exports. EAI pointed out that "with the Strait of Hormuz effectively blockaded, if the Bab el-Mandeb also becomes unstable, the risk of a dual chokepoint, where alternative routes themselves disappear, becomes a reality" [9]. This structural vulnerability elevates the Houthi attacks from a simple local conflict to a matter of global energy and logistics security.

The fact that the Houthis directly targeted Saudi oil facilities is also related to this structure [1][7][10]. The strike on the state-owned oil company's facilities near Abha was a choice aimed at Saudi Arabia's export capacity itself. This can be considered a repetition and expansion of the 2019 attack on the Abqaiq oil processing facilities.

Domestic Political Structure: Saudi Arabia Securing its Rear

Internally in Saudi Arabia, a structural change occurred before this attack. In January 2026, forces of the Southern Transitional Council (STC), which had been supported by the UAE, were ousted from Hadhramaut and Al-Mahra by Saudi airstrikes and pressure from tribal forces [13]. The official dissolution of the STC and the absorption of UAE-backed forces into Saudi Arabia's sphere of influence can be interpreted as Riyadh consolidating its position by eliminating rival factions within Yemen ahead of a full-scale confrontation with the Houthis. This suggests that Saudi Arabia had been anticipating and preparing for this escalation for a considerable time.

3. Historical Precedents and Comparison with Similar Cases

The UN-brokered truce of April 2022 was an exceptionally long-lasting case at the time. The very fact that this four-year truce has collapsed demonstrates the gravity of the current situation. The Sanaa Center recorded that "the arrival of two Iranian aircraft in Houthi-controlled territory in early July triggered a direct Saudi-Houthi engagement on a scale not seen since the April 2022 truce" [11].

The Houthi pattern during the Gaza war also serves as a relevant precedent. EAI noted that this is "an extension of the pattern during the Gaza war where the Houthis threatened the Red Sea-Bab el-Mandeb shipping route by targeting Israel-related vessels" [6]. At that time, global shipping companies suspended Red Sea transits and chose to reroute around the Cape of Good Hope [6]. There is a high probability that the same route avoidance response will be repeated in the current situation.

A historical precedent comparable to the Mecca Defense Pact would be automatic intervention-type alliance systems like NATO's Article 5 or the U.S.-Japan Security Treaty. While the CFR described the Mecca Pact as having a "clause similar to NATO's Article 5" [8], it is fundamentally different from NATO in that actual intervention in the event of an attack depends on political discretion rather than being automatic. Unlike Cold War alliances that built credibility through codified automatic intervention and permanently stationed forces, the Mecca Pact faced its first test just 48 hours after being signed, without even its official text being made public [8][14].

4. Key Variables Shaping Future Developments

The first variable is the direction of the Iran-Oman negotiations over the Strait of Hormuz. EAI noted that "as the Iran war shook the Gulf security landscape, Saudi Arabia moved to secure its own means of deterrence" [6]. If these negotiations reach a settlement, Iran would have an incentive to ease its proxy pressure through the Houthis. Conversely, if the negotiations fail, the likelihood of the pessimistic path presented by EAI—a scenario where "attacks expand to infrastructure across eastern Saudi Arabia" (probability 30-35%)—increases [3][6].

The second variable is whether the Mecca Defense Pact is actually invoked. The Pakistani Defense Minister's statement remains at the level of political rhetoric [17]. Whether Saudi Arabia actually requests the intervention of Pakistani and Turkish forces and whether both countries comply will be the litmus test for whether this pact transitions from a symbol to a substantive reality.

The third variable is the trajectory of the front line for control over the Bab el-Mandeb Strait. The level of risk premium on the Red Sea shipping route will depend on whether the Houthis gain a tangible territorial advantage near the strait or are checked by a counter-offensive from Saudi and Yemeni government forces. Whether there is further intervention, such as the U.S. strike on an Iranian oil tanker, is also a variable that will determine the scope of escalation.

Fourth is the development of the ground war between Yemeni government forces and the Houthis. Amid ongoing clashes around Sanaa's airport and airstrikes on the Hodeidah coast [2][9], the intensity of the conflict in the coming months will be determined by whether the ground war reaches a stalemate or tips in favor of one side.

Implications for South Korea

The structural nature of this crisis lowers the probability of a short-term resolution. As long as Iran’s proxy warfare strategy, Saudi Arabia’s burden of responding unilaterally, and the unverified status of the Mecca Defense Agreement remain in effect, sustained localized conflict and an entrenched risk premium are highly likely to be the baseline conditions for the foreseeable future [3][9]. The South Korean government and companies should prioritize shifting to permanent operations via the Cape of Good Hope route and diversifying procurement sources in eastern Saudi Arabia, rather than basing their response on the assumption that shipping lanes will return to normal [3][9]. Furthermore, a dual-track approach is required, separately monitoring developments among Iranian hardliners and the process of verifying the effectiveness of the Mecca Defense Agreement [3][6].