Editor's note: Richard N. Haass is the president of the Council on Foreign Relations and author of "A World in Disarray." The article reflects the expert's opinions, and not necessarily the views of CGTN.

There are several reasons why U.S. President Donald Trump's decision to withdraw American forces from northern Syria, and leave the region's Kurds vulnerable to neighboring Turkey's military action, was a terrible one. The Kurdish forces in control of the region had been the principal U.S. partner in the struggle against the Islamic State (ISIL). Trump's abandonment of them reinforced already existing doubts in the region and around the world that the United States remains a reliable ally.

The decision also created conditions enabling hundreds, and potentially thousands, of ISIL terrorists in Kurdish-run prisons to go free – and presumably resume terrorist activities as soon as they are given the opportunity. It is more a question of when, not if, U.S. forces will need to return to Syria to contend with a reconstituted ISIL (most likely without a local partner to bear the brunt of the fighting).

In the meantime, the Kurds have turned to the Syrian government for protection against Turkish forces, a move that has allowed President Bashar al-Assad to reassert control over much of the country. For its part, the U.S. has lost most of what leverage it had to influence a political outcome in Syria.

Trump's flawed decision seems to stem from his desire to make good on the promise he made during the 2016 election campaign to withdraw the U.S. military from Syria and the Middle East more broadly. But this raises a larger question: Given the negative impact of the move, why would he believe that it would prove to be popular at home?

One explanation is that Trump is confusing "endless wars" with an open-ended military presence. This confusion is costly. What the U.S. was doing in northern Syria was smart and efficient. Kurdish forces assumed the bulk of the combat role against ISIL; the U.S. contribution was modest and largely confined to advising and providing intelligence support. Moreover, the U.S. presence restrained the actions of the Turks, Syrians, Russians, and Iranians. With the withdrawal of U.S. troops, that restraint disappeared overnight.

More fundamentally, Trump's decision taps into an old American tradition of isolationism, which has a lineage traceable to America's Founding Fathers. It was in remission during the Cold War, but it has recently reemerged, fueled by the "intervention fatigue" triggered by the long and expensive wars in Afghanistan and Iraq. 

It gains additional traction from the widespread view in the country that many domestic needs – from infrastructure to healthcare and education – are going unmet. A lack of emphasis on foreign policy and the world in U.S. schools and media is also contributing to this inward turn.

Trump's "America First" slogan is premised on the idea that the costs of U.S. world leadership far outweigh any benefits. The resources spent on activism abroad, according to this view, would be better spent at home.

However appealing such arguments may sound, the notion that the U.S. can safely turn its back on the world and still thrive even as global order declines is seriously misguided. Trump has repeatedly claimed that Syria is not critical to America's security, noting that it is thousands of miles away. But Americans learned the hard way on September 11, 2001, that distance is no guarantee of safety. Similarly, infectious disease, the effects of climate change, and efforts to subvert elections do not stop at national borders.

The costs of America's global role are considerable by any measure. The defense budget alone now totals 700 billion U.S. dollars annually, and intelligence, foreign aid, diplomacy, and maintaining a nuclear arsenal bring overall national security spending to over 800 billion U.S. dollars. But as a percentage of GDP, this is well below the Cold War average. And history shows that the U.S. economy nonetheless flourished even with this high level of spending.

To be sure, the U.S. has many domestic shortcomings, from public education to health care, but for the most part these problems are not the result of a lack of spending. The country spends over twice the Organization for Economic Co-operation and Development (OECD) average on healthcare, but Americans do not lead longer or healthier lives. Similarly, high spending on education does not yield better results than in countries that spend less. How money is spent is always more important than how much is spent.

But such facts are nearly irrelevant when it comes to the political debate. Many of the candidates seeking the Democratic nomination to challenge Trump for the presidency in 2020 share at least some of his isolationist views, and opinion polls reveal that many Americans do, too. Trump is as much a reflection of America's mood as its driver, and a certain degree of "Trumpism" – a desire to pull back from global commitments in general and military ones in particular – is likely to outlast the man.

At some point, things will change. History suggests that periods of retrenchment often end owing to some great geopolitical shock, followed by periods of exertion. The problem is that such shocks tend to be costly in terms of human lives and resources. But for now and the foreseeable future, the U.S. is unlikely to conduct a foreign policy commensurate with its interests and strength.

Copyright: Project Syndicate, 2019.

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