'We have defeated ISIS in Syria, my only reason for being there during the Trump presidency," U.S. President Donald Trump tweeted triumphantly on December 19, 2018. His decision to withdraw over 2,000 U.S. troops from Syria was later confirmed by the White House. It not only shocked the Washington circles, but will also influence the geopolitical landscape in the Middle East.

Why now?

Trump's decision to withdraw from Syria and partially from Afghanistan is based largely on two assumptions. First, Trump believes that the U.S. presence in the Middle East does not serve its national interests and does not get the proper respect from regional states. Moreover, withdrawing from Syria and Afghanistan was one of his presidential campaign promises and Trump hopes to be perceived as a leader who is "a man of his word."

Second, the U.S. traditional concerns in the Middle East, such as protecting oil supplies and defeating the direct threat of terrorism, have disappeared or are decreasing. The United States has transformed itself from an oil-importing state to an oil-exporting country due to the development of shale oil technology, while the extremist group, the Islamic State of Iraq and Syria (ISIS), is also disappearing with years of global terrorism combating efforts. In recent years, the major targets for ISIS and Al-Qaeda have been shifted from the United States to "takfirs," defined as Muslims who are accused by other Muslims of being non-believers, or apostatic states, countries accused of renouncing Islam, in both Europe and the Arab world.

As the winner of the Cold War, the United States' dominating influence in the Middle East was once accepted by both the region and the international community. It was the United States that led the Gulf War in 1991. It was also the United States that organized the peace process between Israel and Palestine and facilitated the peace negotiations between Israel and Arab states, especially Syria and Jordan in the 1990s. It was the United States that launched the war against Afghanistan under the Taliban in 2001, and Iraq in 2003, and later helped install the new governments and local political systems. It was the United States that wanted to constrain the influence of Iran in the Middle East and initiated sanctions against Tehran. It is not an exaggeration to say that the United States has constructed the Middle East's regional and geopolitical structure since the 1990s.

Trump has his own explanations for his decision to withdraw, but he still faces tremendous pressure at home. U.S. Defense Secretary Jim Mattis resigned after Trump's announcement as did U.S. special envoy for the coalition to counter ISIS Brett McGurk.

For many U.S. diplomats and foreign policy experts, staying in Afghanistan and Syria has meant maintaining U.S. dominance in the region and repelling the influence of its regional and international competitors, especially Iran and Russia. Trump's decision to withdraw creates a sudden geopolitical vacuum in the region, with the U.S. reputation and influence in the region set to be further challenged.

Regional competition

The U.S. withdrawal marks an important step in changing the geopolitical balance in the Middle East, and will lead to a new round of competition and rivalry among regional powers, especially Turkey, Iran, Saudi Arabia and Israel.

Turkey believes the Syrian Kurdish Democratic Union Party (PYD) is a branch of what it terms a terrorist group at home, the Kurdistan Workers' Party (PKK), and is determined to eliminate it from north Syria through military offensives. Turkey launched two major offensives in 2016 and early 2018 to expel the PYD-dominated militant groups from north Syria. It hopes to establish a buffer zone in north Syria across the entire Syrian-Turkish border to settle both the Syrian rebels it backs and the 3.5 million Syrian refugees currently in Turkey.

It was Turkey that successfully persuaded Trump to withdraw from Syria and is preparing for a military offensive in north Syria after the withdrawal. Once Turkey launches its military offensive, it may lead to a new round of regional competition or even conflict.

The Syrian Government still insists on its legal claim over all Syrian territory. From the 1980s to mid-1990s, the PKK and the Syrian Government had very close relations and north Syria was once an important base for PKK militias to infiltrate into south Turkey to launch attacks. After the Syrian civil war erupted in 2011, Syrian forces withdrew from north Syria and Syrian Kurds led by the PYD became the dominating

power in the area. Many analysts believe the PYD has been a close ally of the Syrian Government during the civil war, while others dispute that. If Turkey intends to dominate the whole of north Syria, the Syrian Government may offer assistance to the PYD. This may lead to Iran and Russia having to reconsider their policies toward Syria and making a choice between staying neutral and supporting the Syrian Government.

Iran and Russia have been important supporters of the Syrian Government, but their interests in Syria may not be in accordance with the interests of the Syrian Government.

Russia has repeatedly expressed its willingness to help organize a transition government based on a new constitution coordinated by the United Nations-mediated Syria Constitution Committee, which the Syrian Government strongly objects to. Russia hopes to facilitate the political reconstruction process in Syria and strengthen its influence in the country. Although Iran has been a steadfast supporter of the Syrian Government since 2011, its financial and social difficulties at home limit its involvement on the Syrian battlefield. Although Iran and Russia may not directly confront Turkey in north Syria, they may support the Syrian Government indirectly against a Turkish offensive and Ankara-backed rebels.

A future U.S. return

Israel is also closely monitoring the latest developments in Syria. As the ties between Turkey and Israel grow more strained over the Israeli-Palestinian peace process and Turkey's sympathy toward the Islamic extremist groups in Syria, Israel worries that the expansion of Turkey's influence in Syria may help turn north Syria into a hub and base for extremists and terrorists and pose a threat to Israeli security. When the regional status quo in Syria is changed and a new round of competition erupts, regional states will need to get involved. As the most powerful state in the world, the United States might have to return.

Although Trump tries to describe his decision to withdraw from Syria as an important step in "making America great again" based on the "America First" policy, it may be understood by U.S. partners and allies such as Saudi Arabia, an important U.S. regional ally, for decades, as the beginning of a betrayal and desertion.

Saudi Arabia regards the United States as its most reliable partner, but once the U.S. dominance in the Middle East collapses, it may have to choose to cooperate with other states, such as Russia, to ensure its own national security and the overall regional geopolitical balance. The huge amount of Saudi military purchases from U.S. weapons factories may be replaced by Russian ones. If Trump wants to keep the billions of dollars from the Saudi weapons market, he will have to do more to show U.S. capabilities in the region to meet the expectations of Saudi Arabia.

In international politics, capability matters more than willingness. A state with more capabilities usually leads to more expectations from other countries. In the modern world, a state's capabilities are generally constructed from its connections with the rest of the world, especially its close cooperation and ties with other states, which ultimately lead to a big network throughout the world. No state in the modern world can be "great" without major ties to the outside world. Therefore, Trump's decision to withdraw may be a bad choice for the United States, and he may have to say, in the not so distant future, that the United States will return.

The author is a research fellow at the Charhar Institute and the University Haifa in Israel

Copyedited by Rebeca Toledo

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