Afghan National Army officers march during a training exercise at the Kabul Military Training Centre in Afghanistan in this, October 7, 2015.
Ahmad Masood / Reuters

Saudi Arabia and Iran’s ongoing proxy war in the Middle East is never far from the headlines. The two countries have sparked or exacerbated various conflicts throughout the region, including in Syria and Yemen, two of the most complex and devastating wars in recent history. But another battle between the two regional powerhouses has gone relatively unnoticed, even though it could further destabilize a key strategic theater for the West: Afghanistan.

Since entering Afghanistan nearly 15 years ago, NATO has committed thousands of troops and billions of dollars to the country. Today, 13,000 NATO troops remain there, and this summer, NATO committed to continue funding Afghan forces until 2020.

But despite all these efforts, Afghanistan remains highly volatile, with a weak central government and various insurgency groups that maintain considerable influence in the country. Many of these groups have a long history of working with Tehran or Riyadh and sometimes both. Although both capitals fund Islamic centers and various groups in Afghanistan, their respective strategies for the region diverge considerably.

Iran sees Afghanistan as a primary zone of influence, much as it sees Iraq. The two countries share a porous border, as well as cultural, linguistic, ethnic, and economic ties. Iran is also home to a large number of Afghan refugees, and increased instability and insecurity there translate into even more. Further, narcotics trafficking from Afghanistan fuels Iran’s epidemic of drug abuse. For these reasons, Tehran was already present in Afghanistan when the United States and its NATO allies intervened in 2001. At the time, Iran saw the NATO war as an opportunity and worked with Washington and its partners to defeat the Taliban and stabilize the country. Tehran also leveraged its influence to help build a new national government in Kabul and donated hundreds of millions in aid. Iran has often been a helpful force in Afghanistan, unlike in other similar conflicts it’s involved in, such as Syria.

Saudi Arabia has a long history in Afghanistan as well. Riyadh and private Saudi citizens and charities have spent substantial money in Afghanistan since that country’s war with the Soviet Union. For example, the Saudis promoted Afghan jihad in the late 1980s and early 1990s, and the kingdom was the second country to recognize the Taliban government in the late 1990s. Today, Riyadh also has interests in Afghanistan, but it doesn’t see the country as a main theater of influence. In fact, Afghanistan is to Saudi Arabia what Yemen is to Iran: the top priority for its key adversary, where it can project power without much effort. As a result, the kingdom can use Afghanistan to poke Iran in the eye, especially as Iran does the same in Yemen.

The United States and its NATO allies must begin to address the areas where Tehran and Riyadh’s competition can destabilize Afghanistan.

Afghanistan has another key advantage for Riyadh: it is important to the United States. Riyadh increasingly believes that it is being abandoned by the United States, and so it seeks ways to assert itself. The recently passed Justice Against Sponsors of Terrorism Act, which allows U.S. citizens to sue foreign governments (clearly targeting Riyadh) for terrorist attacks perpetrated on U.S. soil on September 11, 2001, further frustrated the Saudi government, potentially giving it all the more reason to assert itself. Afghanistan is the perfect place to do so. Saudi Arabia can leverage the groups it’s been funding and supporting to further destabilize Afghanistan, especially in the rural areas, challenge the central authority, and thus disrupt U.S. and NATO efforts to stabilize and develop the country.

But Afghanistan could also become a bargaining chip for Riyadh: Saudi Arabia could use it in possible future negotiations with Washington on military cooperation or with Tehran over regional security. The kingdom could leverage Afghanistan to get more support or military aid, equipment, and weapons from the United States and a reduced presence in Yemen from Iran.

Tehran’s and Riyadh’s competition in Afghanistan could translate into increased direct and indirect funding and support for various Islamic centers and insurgency groups. Saudi Arabia works mainly with Sunni groups, but Iran works with a number of groups, both Shiite and Sunni (even terrorist groups with anti-Shiite agendas). The growing presence of the Islamic State (also known as ISIS) could encourage Iran to increase its presence there. Iran wants to avoid being sandwiched between two areas of ISIS influence or control. With ISIS still holding swaths of territory to its west in Iraq, Iran wants to avoid having Afghanistan also fall to the group. Moreover, Tehran wants to prevent a rollback in the progress made in Afghanistan and avert further destabilization. To achieve these goals, Iran might start working with groups that it doesn’t see eye to eye with (such as the anti-Shiite Hezb-e Islami) and may begin to let the Revolutionary Guard Corps become more visibly active there, as it has in Iraq and Syria.

Meanwhile, Saudi Arabia sees Iran as its number one security threat. This perception is reinforced by the conviction that the kingdom is losing its greatest asset: Washington, which it believes no longer cares about the Middle East. As a result, Riyadh is eager to project power and assert itself while frustrating Iran. For its part, Tehran’s main security concern lies in the weakening and collapse of its neighbors’ central authorities, which leaves a vacuum in which terrorist groups can operate and expand freely. Consequently, Tehran sees Afghanistan as its top priority and wants to make sure that ISIS doesn’t gain a proper foothold there.

It’s no secret that Washington no longer has the leverage it once had over the Saudi establishment. For its part, Riyadh’s security calculations are driven by a willingness to assert itself as a force to be reckoned with. Today, Saudi Arabia’s hopes of a decisive victory in Yemen seem increasingly unrealistic. Afghanistan may thus become the new battleground, where Riyadh thinks it can hit multiple targets on its agenda at a lower cost. Riyadh is continuing its funding and support for various groups in Afghanistan and expects to see results. It can ask them to frustrate NATO efforts to strengthen the central authority and stop militias from gaining ground. Far from the field, Riyadh has also started to attend multilateral diplomatic sessions on the future of Afghanistan.

A decade and a half after the NATO intervention in Afghanistan, the possibility of a Saudi-Iranian proxy war in the country adds a new layer and threat to an already complex and volatile situation. The United States and its NATO allies must begin to identify and address the key areas where Tehran and Riyadh’s competition can destabilize the country. They must also be aware that the window of opportunity for any discussion between the two countries is closing fast. Iranian presidential elections are approaching, and the country’s moderates who are still willing to engage with Riyadh are under pressure from domestic factions. While Riyadh is at the table and Tehran is still willing, the United States and its NATO partners must push the two sides to begin to talk before it’s too late.

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  • ARIANE M. TABATABAI is Visiting Assistant Professor at Georgetown University's School of Foreign Service in the Security Studies Program.
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