Yemen, a failed state embroiled in a bitter civil war, has become infested with terrorist groups and multiple overlapping insurgencies. The chaos has allowed Al-Qaeda in the Arabian Peninsula (AQAP) to flourish and develop into one of the most potent terrorist threats to the United States.

The paramount U.S. national security interest in Yemen is to defeat AQAP while backing Arab efforts to support the internationally recognized Yemeni government, which is more focused on battling Iranian-supported Houthi rebels than it is on AQAP. Washington also should work to contain Iranian influence in Yemen, but that is more likely to come through a political settlement that tamps down the fighting than it is through an unlikely military victory by the weak Yemeni government and its Arab allies.

Dancing on the Heads of Snakes

Yemen’s government, undermined in 2011 by Arab Spring protests against corruption and poor governance, dissolved into warring factions and attracted the intervention of rival foreign powers. Former President Ali Abdullah Saleh, who once said that ruling Yemen is “like dancing on the heads of snakes,” was forced out of power by protests in 2012. He then joined with Iran-backed Houthi rebels, which his government had been fighting on and off since 2004, to overthrow his successor, Abed Rabbo Mansour Hadi, and seize Yemen’s capital, Sanaa, in September 2014.

Hadi fled to Saudi Arabia and returned to Yemen with the support of an Arab military coalition led by Saudi Arabia and the United Arab Emirates (UAE) in 2015. While the UAE has led an effective and realistic campaign against AQAP in southern Yemen, Saudi Arabia has had much less success in pushing back Houthi–Saleh forces from the mountainous territory they seized in central and western Yemen. The Saudi-led campaign there has bogged down in a stalemate. More than 10,000 Yemenis have died in the fighting, and a humanitarian catastrophe is brewing, with over 60 percent of Yemenis—more than 17 million people—estimated to be at risk of starvation.

Yemen, Osama bin Laden’s ancestral homeland, has long been a hotbed of Islamist extremism and support for al-Qaeda.[REF] Al-Qaeda’s first terrorist attack against Americans occurred in Yemen in December 1992, and it launched a devastating attack in Yemen in October 2000 when it bombed the USS Cole in the port of Aden, killing 17 American sailors. AQAP has pioneered the use of sophisticated bombs that are difficult to detect, such as the one used by the so-called underwear bomber who tried but failed to explode a bomb in an airliner over Detroit on Christmas day in 2009. AQAP’s bomb-making expertise has prompted stronger security precautions on commercial airliners, and the organization remains one of the world’s most dangerous terrorist groups.[REF]

A U.S. Policy for the Yemeni Snake Pit

Yemen’s civil war has created an increasingly permissive environment for Islamist terrorist groups, similar to civil wars in Libya, Syria, and Somalia. The Administrations of Presidents George W. Bush and Barack Obama worked with Saleh’s government to encourage it to take a more confrontational position against al-Qaeda. American special operations forces trained elite Yemeni counterterrorism forces, but that ended after the collapse of the Yemeni government.

After the 2015 Saudi-led intervention, the Obama Administration provided intelligence, logistical support, and aerial refueling for the Arab coalition forces, but the White House froze the transfer of precision-guided munitions and pulled back on intelligence support after the Saudi air campaign was criticized for causing heavy civilian casualties.

The Trump administration lifted the freeze on munitions and announced a new round of arms sales to Saudi Arabia during President Donald Trump’s recent visit there. While the Obama Administration pulled back on U.S. air and drone strikes against AQAP, the Trump Administration has expanded the campaign to include the targeting of mid-level leaders of its guerrilla army. The Pentagon launched a special operations raid against an AQAP compound in central Yemen on January 29 as well as at least one other raid in May, the first reported operations involving U.S. troops since 2014.

To maintain the pressure on AQAP and address other security concerns stemming from Yemen’s complex, multisided war, Washington should:

• Make the defeat of AQAP the top U.S. priority. The Trump Administration should escalate air strikes, drone strikes, and special operations raids against AQAP leaders while working to shape a less permissive environment for transnational terrorists. It should provide enhanced training to Saudi, UAE, and Yemeni counterterrorism forces and cooperate closely with them in targeting AQAP.

Military efforts, however, must be reinforced with soft-power efforts to reshape Yemen’s political environment. The Yemeni government has tacitly cooperated with AQAP to battle southern secessionists and Houthi–Saleh forces. For example, AQAP plays an important role in fighting Houthi forces in Taiz city in central Yemen and has operated in close coordination with the Abu Abbas brigade, a Salafi militia backed by the Arab coalition.

The United States should use carrots and sticks to discourage covert government cooperation with AQAP and encourage tribal opposition to AQAP. For example, tribes in Shabwah governorate in eastern Yemen mobilized against AQAP to prevent U.S. air strikes on tribal territory. Washington should also work with Saudi Arabia and the UAE to twist Yemen’s tribal kaleidoscope in a more favorable direction. The CIA should coordinate efforts to reach out to tribal leaders and provide financial inducements to turn them against AQAP, which has benefitted from their frequent unwillingness to support the Yemeni government against it.

• Contain and roll back Iranian influence. Iran sees the Yemen conflict as a convenient means of outflanking and undermining Saudi Arabia, its principal Arab antagonist. Tehran also may seek to tie down Saudi and Gulf Cooperation Council (GCC) forces in Yemen to constrain their ability to intervene in Syria against Iran’s ally, the Assad regime. Iran’s military footprint in Yemen is relatively small, particularly compared to Saudi Arabia’s much greater military involvement. Iran supports the Houthis with arms, training, technical expertise, and funding. Iranian Revolutionary Guards and Hezbollah proxies have trained Houthi fighters in Iran and Yemen.

For Iran, the Houthis are useful allies, not mere proxies. They are motivated primarily by regional grievances and are Zaidi Shiites who do not share Iran’s Twelver Shiite religious heritage, although they have professed a radical Shiite Islamist view of the world. Tehran may have plans to recruit Houthis to build a more extremist faction that would be more pliable, similar to how it recruited elements of the Amal movement in Lebanon to create the more extremist Hezbollah.

The Trump Administration should assist the military efforts of the Arab coalition to restore the internationally recognized government of Yemen, but it should stop short of deploying U.S. ground troops in a stalemated, open-ended conflict. Washington should provide enhanced intelligence support, drone reconnaissance assets, logistical support, and stepped up naval patrols to intercept ships smuggling Iranian arms shipments off Yemen’s coast.

Washington should also help the Saudis to defend their border with Yemen by providing technology, equipment, and training to enhance border security. The Houthis have launched cross-border attacks that have inflicted heavy casualties on Saudi civil defense forces and civilians.

• Safeguard sea routes off Yemen’s coast. Iran almost certainly played a role in supporting, if not conducting, the failed missile attacks against the USS Mason near the Bab al Mandab Strait on October 9 and 12, 2016. The missiles were likely C-802 Noor anti-ship missiles, which Iran has transferred to Hezbollah. Even if the Houthi–Saleh forces were able to launch the older C-801 missiles that were deployed originally on Yemeni missile boats, the use of ground-based radar systems in the attacks points to technical support by the Islamic Revolutionary Guard Corps or Hezbollah. The Houthis denied that they launched the missiles, but they did claim responsibility for the October 1, 2016, attack on a UAE naval vessel as well as a suicide bombing of a Saudi warship in February 2017.

Although the Houthis have little incentive to risk provoking a U.S. military retaliation, Iran has a much greater incentive to launch missile attacks to demonstrate a capability to disrupt shipping through the Bab al Mandab Strait, a key maritime choke point. Such a capability would enhance Iran’s troublemaking power and increase its potential leverage against the United States and its allies.

Washington and its NATO and GCC allies should beef up naval patrols near the strait to deter and defend against possible future attacks. If another attack is launched, the Pentagon should not only destroy the radar sites involved, as it did after the attack on the USS Mason, but also expand the target list to leave the responsible parties—the Houthi–Saleh forces, Iranian Revolutionary Guards, and/or Hezbollah—in a significantly weakened position.

• Push for a political settlement. Neither the Houthi–Saleh alliance nor the Hadi government is capable of scoring a decisive military victory in the grueling war of attrition. The longer the Yemeni conflict persists, the more AQAP will benefit from the chaos and the more dependent on Iranian support the Houthis will be. The Trump Administration should throw its diplomatic weight behind a political settlement that can halt the fighting, meet Saudi security needs, avert a humanitarian catastrophe, and allow Yemeni factions and the Arab coalition to focus more intensively on fighting AQAP.

The United Nations has sponsored peace talks, but negotiations between the Hadi government and the Houthi–Saleh alliance are deadlocked. What is needed is a decentralized federal political framework that would give local elites, particularly in the South and other predominantly Sunni areas, the power and resources to address festering regional grievances. If not included, southern Yemenis are likely to declare independence, further weakening what is left of Yemen’s splintered government.

A Way out of the Snake Pit

Both AQAP and Iran see Yemen as the back door for subverting Saudi Arabia. The Trump Administration should help Riyadh to secure this door without getting the United States bogged down in an open-ended ground war. Washington should prioritize military campaigns in Afghanistan, Iraq, and Syria while assisting allies in Yemen primarily through the use of air and sea power.

Ultimately, however, it will take substantial diplomatic and economic power, combined with humanitarian aid and long-overdue political reforms, to restore Yemen’s snake pit to a semblance of stability. The United States can provide counterterrorism help, diplomatic support, and humanitarian aid, but Yemenis and their Arab allies must take the lead on other fronts.

—James Phillips is Senior Research Fellow for Middle Eastern Affairs in the Douglas and Sarah Allison Center for Foreign Policy, of the Kathryn and Shelby Cullom Davis Institute for National Security and Foreign Policy, at The Heritage Foundation.