To keep recent rebel victories from cascading into a wider military collapse, Washington must urge the Gulf coalition to firm up the government’s forces and move more quickly on peace talks.

On March 2, Yemen’s Houthi rebels seized the capital of al-Jawf province in the latest phase of a forty-five-day campaign along multiple fronts. Stemming from shifts in the country’s increasingly fragile military balance since last fall, the offensives show that Saudi Arabia is providing insufficient frontline support to the internationally recognized government of President Abdu Rabu Mansour Hadi and its allies, while also failing to complete backchannel peace talks with the Houthis. Unless talks reach fruition or the Houthis are checked militarily, rebel forces will continue to use their ever-widening array of advanced Iranian weapons to exploit the government’s weakness with more offensives.

HOUTHIS EXPLOITING PEACE DELAYS

The Stockholm process that the UN launched in 2018 brought a welcome reduction in fighting, as did Saudi-Houthi moves toward de-escalation last September. At the same time, however, the Houthis have energetically exploited these protracted diplomatic processes and the related military withdrawal of the United Arab Emirates in order to shift the military balance firmly in their favor.

In the first half of 2018, the Houthis were facing Gulf-backed government offensives in nearly a dozen locations, while the coalition air campaign prevented them from massing large offensive forces on any single front. The drastic reduction in this pressure over the past few months has enabled the rebels to regain their operational mobility for the first time since 2015. According to the Yemen Data Project, the volume of coalition airstrikes decreased from an average of 385 per month in the latter half of 2018 to 75 per month in the latter half of 2019; in parallel, the government has shut down almost all of its offensive operations since Emirati forces left last year.

Amid this lull, the Houthis shifted forces from one front to another to achieve local superiority, then mounted successful offensives in the provinces of al-Jawf (March 2019, February 2020), Dhale (March and May 2019), Saada (August 2019), Marib (July 2019 and January 2020), and al-Bayda (January 2020). During the Saada offensive, they encircled elements of three Yemeni army brigades and embedded Saudi Arabian National Guard units in the Kitaf district, located approximately twenty-five kilometers south of the Saudi border; nearly 200 government forces were killed and over 1,300 captured (an unknown number of Saudi personnel were captured as well). More recently, the government lost a heavily fortified defensive bastion in the mountainous Nihm district between Marib and Sanaa in January. Al-Hazm, the capital of al-Jawf and home to nearly 30,000 people, followed earlier this week.

WHY ARE HOUTHI OFFENSIVES MORE EFFECTIVE NOW?

Although the Houthis have always been tough defenders, they did not have a good offensive track record between 2015 and 2018, when the Gulf coalition was paying close attention to frontlines and providing strong air/artillery support and missile defenses. Previous Houthi attempts to break out of their core areas into flat terrain or dislodge government forces from fortified mountain positions around Nihm were repeatedly blunted by coalition airstrikes, with heavy rebel casualties.

Since mid-2019, however, government forces have been greatly weakened by the sharp reduction in coalition airstrikes and the withdrawal of key Emirati “enablers”—namely, strike and intelligence aircraft and joint terminal attack controllers (JTACs) across the theater, as well as Patriot/Pantsir air defenses in Marib and Aden. This drawdown lessened the military pressure on the Houthis and reduced the responsiveness of on-call close air support previously available to frontline government forces.

Another growing problem has been internecine fighting between the secessionist Southern Transitional Council militia and forces loyal to President Hadi and his Islah faction generals. Since capturing the oil-rich Shabwa province from the STC in August, the government has had to keep an additional seven-brigade garrison there to deal with a residual southern insurgency. It has also flowed forces from its manpower reservoir in Marib toward Abyan province, another tense southern frontline with the STC. This flow continued despite the growing Houthi pressure in Marib and al-Jawf. Although additional Hadi forces were recovered to Marib after last summer’s defeat in Aden, they lost their heavy equipment in that campaign, and their return was more than offset by the diversion of other forces, equipment, and ammunition away from Marib.

Meanwhile, the Houthis have acted with growing coherence and military sophistication since late spring 2019, as evident in the following characteristics:

Rapid switching of elite forces between different fronts. Although some of the rebel offensives have overlapped, open-source information and ground reporting from coalition and Yemeni military personnel suggest that a limited cadre of tactical commanders, high-quality fighters, Lebanese Hezbollah advisors, and special weapons are being switched from one point of attack to another.

Although some of the rebel offensives have overlapped, open-source information and ground reporting from coalition and Yemeni military personnel suggest that a limited cadre of tactical commanders, high-quality fighters, Lebanese Hezbollah advisors, and special weapons are being switched from one point of attack to another. Increased use of precision rocket and drone strikes. Since last July, the Houthis have repeatedly launched precise long-range tactical rockets (e.g., the Badr-1P) and tactical explosive drones at local military leadership targets at the beginning of their offensives. This has occurred at least nine times on the Marib and al-Jawf frontline, with accurate strikes on the locations of Marib governor Sultan al-Arada and Defense Minister Mohammed al-Maqdashi (who was lightly injured). Saudi missile defenses have seemingly made no effort to intercept these strikes.

Since last July, the Houthis have repeatedly launched precise long-range tactical rockets (e.g., the Badr-1P) and tactical explosive drones at local military leadership targets at the beginning of their offensives. This has occurred at least nine times on the Marib and al-Jawf frontline, with accurate strikes on the locations of Marib governor Sultan al-Arada and Defense Minister Mohammed al-Maqdashi (who was lightly injured). Saudi missile defenses have seemingly made no effort to intercept these strikes. Exploitation of tribal fault lines. Reflecting their skill at mapping the human terrain of Yemen’s battlefields, the Houthis have effectively splintered government-allied militias during offensives in al-Bayda, Marib, al-Jawf, and Hajjah.

Reflecting their skill at mapping the human terrain of Yemen’s battlefields, the Houthis have effectively splintered government-allied militias during offensives in al-Bayda, Marib, al-Jawf, and Hajjah. Defensive consolidation. The rebels have shown a stronger capability to rapidly consolidate their new territorial gains via tactical minefields, laying large networks of explosively formed penetrators that have blunted government counterattacks. Ongoing U.S. interdictions of Houthi-bound ships have discovered other vital aids to this consolidation, including new types of Iranian-built anti-helicopter or loitering anti-aircraft missiles and large stocks of anti-tank guided missiles.

SPLITTING THE HOUTHIS FROM IRAN

Although the United States is not a combatant in the war, it does have a strong interest in weakening the Houthis’ growing ties with Iran’s Islamic Revolutionary Guard Corps and Hezbollah. On January 3, U.S. forces launched an unsuccessful strike in Yemen against Reza Shahlai, the chief IRGC advisor to the rebels, but concerted efforts will be needed on the diplomatic front to erode these links more substantially (see next section).

The problems posed by this relationship extend well beyond Yemen. So long as Iran continues to arm the rebels in violation of the UN weapons embargo, the Houthi threat to other regional states will grow, from the industrial heartlands and population centers of the Gulf states and Israel to the sea-lanes of the Bab al-Mandab Strait, Suez Canal, Indian Ocean, and Horn of Africa. On February 21, for instance, the Houthis attacked Saudi Aramco oil sites in Yanbu using twelve Sammad-3 long-range drones and two Quds cruise missiles—advanced systems that experts believe were provided by Iran and reskinned with Houthi names.

As for the maritime threat, Iranian versions of the advanced C-802 anti-shipping missile were intercepted en route to the Houthis in January. And on March 4, a Saudi tanker near the Yemeni port of Nishtun was attacked using multiple explosive drone boats launched from a mothership—a refined version of a tactic that the Houthis have been using since 2016, but now capable of being launched over 800 miles away from their Red Sea ports.

FREEZE FRONTLINES, BE SPECIFIC IN PEACE TALKS

Because the fighting in Yemen has arguably tightened IRGC links to the Houthis, it is in America’s strategic interest to end the war—albeit not with a Houthi victory. Iranian-backed Houthi hardliners will adopt an even more obdurate position if they continue to pay no cost for mounting regular, successful offensives. The United States should therefore do what it can to speed up Saudi diplomacy and slow down rebel military advances.

This includes working more urgently with Riyadh to formulate an explicit backchannel offer to the Houthis, calling on them to significantly degrade their ties with Iran while offering real compensation in forms both intangible (respect, recognition, reassurance) and tangible (reconstruction, ceasefire). If the Saudis continue to dither, Yemeni spoiler factions on both sides will keep trying to benefit from the war by provoking and escalating hostilities.

In parallel, Washington should privately advise Saudi Arabia to restart frontline defensive air and artillery support. This could help offset Houthi advantages, interdict Houthi operational redeployments, freeze the frontlines, and restore some defensive resilience to the Hadi government.

A renewed Emirati role is even more desperately needed. In addition to bolstering the air campaign, the UAE should be encouraged to augment Saudi air defenses with top-tier PAC-3 missile systems in Marib—a low-risk, high-payoff mission that could reassure the local military leadership while protecting the province’s major oil and gas infrastructure.

None of these steps would place U.S. troops in harm’s way. Rather, they provide a thrifty way to stop Iran from giving the Houthis more battlefield victories.

Alex Almeida is the head security analyst at a leading risk advisory firm. Michael Knights is a senior fellow with The Washington Institute. Both authors have visited Yemen and the Gulf coalition states on multiple occasions and observed military operations on a variety of fronts.