By/April Longley Alley*

Among the broader regional repercussions of the Gaza ceasefire in October, one of the most significant was expected to be the emergence of a new calm in the Red Sea region ,and possibly in Yemen. 

Indeed, as a result of the truce, the Houthis, the heavily armed group controlling northern Yemen including the capital Sana’a, and linked to Hamas and Iran, halted their attacks on commercial shipping in the Red Sea and on Israel.

A previous Oman-mediated agreement between the Houthis and the U.S. government also appeared to reduce the group’s direct threat to American assets in the shipping corridor. 

Inside Yemen, a fragile three-and-a-half-year truce between the Houthis and the internationally recognized government remained in place. Although the Houthis had not been defeated, U.S. officials seemed to believe the situation had stabilized enough to shift their attention elsewhere.

But less than two months later, that relative calm began to unravel. In early December, southern separatists launched a major campaign to seize large parts of Hadramawt ,the oil-producing region bordering Saudi Arabia ,and Al-Mahra, which borders Oman. 

The offensive, led by the Southern Transitional Council (STC), a body formally part of Yemen’s internationally recognized government but advocating for southern independence, marked a seismic shift in the country’s balance of power. 

Backed by the United Arab Emirates, the STC’s bold expansion sparked new tensions with Saudi Arabia, which supports rival factions within the government and views the takeover as a potential threat to its national security. More troubling still, the STC’s offensive is likely to provide the Houthis with a pretext for broader moves.

As the STC campaign unfolded, the Houthis pledged to expand their control over Yemen’s oil and gas-producing regions in the east.

With support from Iran and other actors, the Houthis have worked tirelessly to expand their arsenal of advanced conventional weapons. They have ramped up domestic weapons production, gained the ability to assemble ballistic missiles, and manufacture short-range drones independently. 

Their actions and rhetoric continue to underscore ambitions to dominate all of Yemen and confront Israel, the United States, Saudi Arabia, and the UAE.

If the Gaza truce collapses, the Houthis are prepared to resume their Red Sea attacks. Having seen the effectiveness of that campaign, they may relaunch it in the future for other reasons.

U.S. neglect of Yemen carries serious risks. So far, the Trump administration has limited itself to imposing sanctions on the Houthis, maintaining the bilateral truce, and hoping Israel and Washington’s Gulf partners would handle the rest. 

The administration has largely withdrawn support for Yemen’s government and abandoned a leading diplomatic role in ending the civil war.

Without a broader U.S. strategy, financial pressure on the Houthis could backfire. Even before the STC’s December move, Houthi leaders hinted at seizing more territory or extorting financial concessions from Saudi Arabia to secure additional resources. 

Now, southern unrest has made the country more combustible, threatening to reignite a conflict that has long played to the Houthis’ advantage. Any return to full-scale war would reverberate across the Gulf and the Red Sea region.

Axis of Challenge

As the dust of Israel’s war in Gaza settles, the Houthis stand out as a striking exception. With Hamas weakened, Hezbollah in Lebanon dealt heavy blows, Bashar al-Assad’s regime in Syria collapsing, and Iraq’s Shiite militias avoiding confrontation with Israel, the rest of Iran’s “Axis of Resistance” has been severely diminished. 

In contrast, the Houthis emerged emboldened by the Gaza war, which allowed their leaders to harden the group’s ideological core, sideline pragmatists, and reinforce supporters’ conviction that they are on a religious mission to liberate Palestine and overturn a regional order dominated by the United States and Israel.

The Houthis have reaped tangible gains from this challenge. By remaining in a state of war mobilization, they avoided accountability for worsening poverty and their failure to pay public sector salaries in areas under their control. 

They exploited the conflict to suppress perceived enemies, narrow political opposition, and tighten their grip on power. At the same time, their prominent confrontation with Israel boosted military recruitment ,including child soldiers , facilitated training, and indoctrinated a new generation. By 2024, the Houthis’ fighting force was estimated at around 350,000.

The Houthi threat has grown alongside their expanding military capabilities. 

In the early stages of the Gaza war, their missiles largely failed to reach Israeli territory. But by May 2025, they were able to strike Ben Gurion Airport near Tel Aviv. 

In September 2025, Houthi drones penetrated Israeli air defenses, injuring more than 20 people in Eilat and hitting nearby Ramon Airport. Houthi missiles also struck Yanbu, a major Saudi oil port roughly 620 miles from Yemen’s border. 

Meanwhile, the Gaza conflict provided the Houthis with valuable operational experience, improving targeting accuracy and testing new weapons, including ballistic missiles equipped with cluster munitions.

To expand their arsenal, the group diversified its supply chains and established ties with multiple U.S. adversaries, including China and Russia alongside Iran.

For years, Tehran has provided the Houthis with conventional weapons and training, deepening its support as the rest of its regional axis weakened.

But the Houthis have also begun importing dual-use components and military materials from China for local manufacturing. In September, the U.S. Treasury Department imposed sanctions on 32 individuals and entities linked to the Houthis ,including several based in China, for illicit fundraising, smuggling, and weapons procurement.

Russia, according to The Wall Street Journal, shared targeting data through Iran’s Revolutionary Guard to help the Houthis strike Western vessels, and also delivered oil to the group via the port of Hodeidah. 

In Somalia, the Houthis supplied weapons and training to the Sunni jihadist group al-Shabaab in exchange for money and the prospect of a partnership to disrupt navigation in the Gulf of Aden. 

Somalia has also become a key transit hub for smuggling arms into Houthi-controlled areas.

Houthi leader Abdul-Malik al-Houthi has made clear that the group’s ambitions extend beyond Yemen’s borders. Uniting the Islamic world against Western influence and Israel has been part of the group’s ideology since its inception in the early 2000s ,a goal magnified by the Gaza war. Al-Houthi declared that further rounds of fighting with Israel are “inevitable,” describing Saudi Arabia and the UAE as “tools” in a U.S.-Israeli regional project and traitors to the Palestinian cause. 

He now claims his movement is training more than one million “mujahideen,” and that Houthi-controlled Yemen leads the Arab world in military production and manufacturing. While these assertions are clearly false, they serve to reinforce the Houthis’ self-image as the foremost Arab “resistance” force.

Pressure Without Policy

Despite their rising profile, the Houthis have suffered blows. Operation Rough Rider ,a 52-day intensive bombing campaign launched by the Trump administration in March ,destroyed numerous weapons depots and manufacturing facilities, though the full extent of the damage remains unclear. 

The group’s re-designation this year as a Foreign Terrorist Organization also imposed economic pressure on its territories by cutting access to the international banking system.

Since the summer of 2024, Israeli airstrikes have inflicted significant damage on Houthi-held areas, shutting down the north’s only international airport, destroying large parts of Hodeidah port, and crippling the electrical grid. 

Israel also successfully targeted Houthi leadership; in August, the prime minister and other members of the Houthi-run Sana’a government were killed, though none were core ideological figures. 

In October, the Houthis confirmed the assassination of their chief of staff, a key military strategist. While these strikes only partially reached the top leadership, they forced commanders into hiding, slowed communications, and fueled rumors of further losses.

Washington’s approach to Yemen, however, is riddled with contradictions. 

The bilateral truce with the Houthis in May provided a quick exit from Operation Rough Rider, which cost over $1 billion and drained military assets needed elsewhere. 

Yet it did not prevent the Houthis from continuing attacks on non-U.S. targets in the Red Sea, nor from launching additional missiles and drones at Israel. 

Nor did it establish a long-term strategy to safeguard U.S. interests in the Red Sea or the Gulf.

On the contrary, the truce allowed Washington to politically and militarily disengage, enabling the Houthis to escalate battles against domestic and regional rivals at lower cost. 

The problem was compounded by the administration’s suspension of most humanitarian aid to Yemen, including to government-held areas it claims to support. 

In a country where 24 million people ,most of the population ,require humanitarian assistance, and more than 14 million need urgent aid, this was a devastating blow.

At the same time, tighter sanctions and the closure of diplomatic channels to the Houthis have eliminated any immediate prospect of a negotiated peace. 

The U.S. no longer has a dedicated envoy for Yemen, signaling the issue’s declining priority. Nor does the administration support a return to the pre-Gaza formula of ceasefire and political engagement in exchange for financial incentives, including public sector salary payments. Few in Washington are working on an alternative path.

A New Power Struggle

With renewed unrest in the south, the United States and its Gulf allies may face a broader crisis. The UAE and Saudi Arabia may attempt to contain the fallout from the STC’s takeover of Hadramawt through a joint agreement to manage tensions within Yemen’s government. 

Such an arrangement could create a more unified front against the Houthis, potentially reviving a political settlement track or enabling efforts to reclaim northern territory before any future negotiations.

STC President Aidarous al-Zubaidi has declared that “the next target must be Sana’a, peacefully or through war.” 

Any arrangement allowing STC forces to support fighters along the Red Sea coast and in Marib to retake the north would be extremely difficult, likely requiring guarantees of southern autonomy and possibly a future referendum. But none of this is feasible until the Hadramawt deadlock is resolved in a way that addresses Saudi security concerns.

Time may be running short. 

There is also a real possibility of fighting erupting among government factions, which could allow the Houthis to gain further ground. If the STC were to declare independence ,a step it currently avoids due to slim chances of international recognition ,it could trigger northern forces to realign against it.

In the absence of U.S. engagement, Saudi Arabia and the UAE will continue supporting rival factions. 

Even if the Southern Transitional Council’s campaign does not ignite a wider war, the Houthis will soon need to ease economic pressures on themselves, which could mean seizing additional resources inside Yemen such as attempting to take control of oil-rich Marib or forcing Saudi Arabia into new financial concessions.

The Houthis have openly threatened Riyadh, demanding a permanent end to the war, the lifting of restrictions on ports and airports, and compensation for damages caused by airstrikes between 2015 and 2022. Their messaging including re-circulating footage of past attacks inside Saudi Arabia and strikes on Aramco facilities underscores their readiness to use force.

Given Riyadh’s focus on domestic priorities and growing doubts about the U.S. security umbrella, Saudi Arabia may yield to this pressure.

Although any Houthi expansion would face internal Yemeni resistance, Riyadh may hesitate to back these forces for fear of renewed attacks. Instead, with the government’s position weakened by the STC’s moves in the south, the Houthis may seek gains by courting tribal leaders loyal to the government around Marib.

Any of these paths would provide the Houthis with greater resources to arm themselves for future rounds against the United States and its partners, while further reducing prospects for a comprehensive political settlement.

Israeli leaders have vowed to punish Houthi leadership for their bold attacks, and the government has established a new intelligence unit focused on Yemen. If the Gaza truce collapses, clashes between the Houthis and Israel will resume, potentially distracting the Houthis from other fronts and creating military opportunities for their Yemeni rivals.

But Washington cannot rely on Israel alone to address the Houthi challenge.

The Houthis are geographically distant from Israel and entrenched in mountainous terrain reminiscent of Afghanistan. As Saudi and U.S. campaigns have shown, they cannot be defeated by airstrikes alone. Moreover, Israel is deeply unpopular in Houthi areas, and further strikes—especially against civilian infrastructure—could mobilize Yemenis against a despised “external enemy.” Even if Israel succeeds in additional high-level assassinations, this could produce a more hardline Houthi leadership in Sana’a or trigger internal power struggles that destabilize the region in new ways.

From the Ground Up

Washington’s desire to avoid costly entanglement in Yemen is understandable. Nearly two months of intensive U.S. bombing last spring inflicted damage on the Houthis without altering their behavior or grip on power.

The STC’s campaign highlights growing fractures within the coalition backing Yemen’s internationally recognized government, and the complexity and volatility of internal politics. 

Yet given Yemen’s strategic location along the Red Sea corridor and its proximity to Washington’s Gulf allies, the Trump administration cannot afford a policy vacuum.

To prevent a wider explosion, the United States must recommit serious attention to Yemen. Urgently, it should press Saudi Arabia and the UAE to de-escalate in the south and reach a joint approach, as a prerequisite for effectively addressing the Houthis.

In parallel, U.S. support should help pro-government Yemeni forces secure critical frontlines in Marib and along the Red Sea coast to pressure the Houthis into concessions. Strengthening U.S. security guarantees for Saudi Arabia and the UAE could play an important role, reassuring both countries that Washington will defend them if they face Houthi attacks.

A dedicated diplomatic track must also be revived. Yemen has been at war for more than a decade, and the immense toll on its population will reverberate across generations. The Houthi challenge and Yemen’s broader internal crises cannot be solved by economic pressure or external bombing alone. Coercion is necessary, particularly political and military pressure on the ground from Yemenis themselves, but opening exit routes and diplomatic channels is equally vital.

For this reason, the United States should coordinate with all key stakeholders Yemeni actors, Saudi Arabia, the UAE, Oman, the United Nations, and others to craft a revised settlement.

The Trump administration must recognize that the post-Gaza regional security order it seeks to build will not succeed if Yemen slides into chaos. Without U.S. involvement, Saudi Arabia and the UAE will continue backing rival groups within the government, deepening tensions between two of Washington’s main allies (as seen in Sudan), widening divisions among Yemenis, and creating opportunities for the Houthis and other violent groups such as al-Qaeda to exploit the situation. This could lead to renewed Houthi operations across the region.

Restoring calm in Yemen will not be easy. It will require security guarantees for the Red Sea and Gulf neighbors, and addressing the STC’s demands for southern independence. Ultimately, it will necessitate integrating the Houthis into a political process and refocusing them domestically by giving them a stake in a better future.

The deal may falter amid conflicting interests, but inaction would be far worse, virtually ensuring Yemen’s crises continue spilling into one of the world’s most vital shipping corridors and the wider Middle East. Washington need not lead the Yemen file, but the risks are too great to justify absence.

Source: Foreign Affairs \ a leading American magazine focused on foreign policy and international relations, published by the Council on Foreign Relations (CFR). It serves as a key platform for decision-makers in the United States, featuring in-depth analyses written by heads of state, ministers, diplomats, and strategic experts. The magazine directly contributes to shaping debates and guiding the overall direction of U.S. foreign policy and national security.

*April Longley Alley is a Senior Fellow at the Washington Institute and served as the chief political advisor to the UN Special Envoy for Yemen between 2020 and 2024.