The Revival of Isolationism under the Trump Administration

: Since taking office, Trump has adhered to the policy tenet of America First, with unilateralism as the course of action. At the same time, the Trump administration is also deliberately reducing the international responsibilities borne by the US and emphasizing the principles of fairness and transaction in foreign dealings. Some scholars see this series of actions as a trend towards a return to isolationism. This paper revolves around isolationist foreign policy, more focuses on the revival of isolationism since the Trump administration took office, discusses the Trump administration's foreign policy with its isolationist character. This paper further points out that, given the relative weakening of US international influence, the loss of US manufacturing and the decline in people's living standards, and Trump's mercantilist overtones, the Trump administration has changed its long-held liberal internationalist diplomatic course in favour of a partial return to traditional isolationism. It has profoundly affected the US domestic and world landscape. This study can help to understand the shift in the guiding philosophy of US diplomacy and provide background information on how to develop relations with the US in the new context.


Introduction
Since Trump took office, a series of "retreats" and protectionist trade policies have prompted several scholars to examine his isolationist overtones. For example, Haass argues that Trump's foreign policy is markedly different from that of his four predecessors -George H. W. Bush, Bill Clinton, George W. Bush, and Barack Obama -who tended to combine realism, idealism, and humanism to guide US foreign policy [1]. Kupchan also illustrates Trump's embrace of older diplomatic thinking, including isolationism, through the lens of his withdrawal from international organizations and his emphasis on American identity [2]. However, such studies have not systematically focused on the revival of Trump's isolationism. This paper uses American isolationism as a research theme, it focuses on how the revival of isolationism has manifested itself during the Trump presidency and what has contributed to this revival. This is necessary as it can help to provide a greater understanding of the diplomatic character of the Trump years and the impact the Trump legacy has had on the Biden administration, further providing clues to anticipate the future direction of diplomacy.

The Trump Administration's Return to Isolationism
Isolationism is often referred to as "the political principle or practice of showing interest only in your own country and not being involved in international activities" [3]. Its origins in the United States can be traced back to the time of George Washington. In his farewell address, Washington stated that "the highest rule of action to be followed in the treatment of foreign countries is to expand our trade relations while avoiding political connections as far as possible" and that "our true policy is to avoid permanent alliances with any part of the outside world" [4]. The United States at that time needed to strengthen its economy while avoiding involvement in the war in Europe. After that, it became one of the traditional guiding ideas of American foreign policy. After World War I, America's domestic war aversion and economic woes brought its isolationism to a new climax. It was not until the attack on Pearl Harbour in 1941 that the US became actively involved in international affairs, joining the Allies in the war effort. After World War II, the United States became the only superpower among the Western nations. To avoid the tragedy of the World War and to build a new international order to promote the prosperity and stability of the international community, the United States gradually adopted liberal internationalism as the leading diplomatic guiding ideology. It advocates collaboration with other countries and promotes liberal values such as open markets, the rule of law and democratic governance. As the "benevolent hegemony", the US provides international security and public economic goods abroad, assuming the role of leader in maintaining the liberal international order [5]. However, the "America First" diplomacy that Trump has been promoting since he took office has tended to return to traditional isolationism. This, in turn, has manifested itself in the following ways.

Adherence to Nativism and Emphasis on American Identity
In his inauguration speech, Trump made clear his America First policy orientation. He advocated "buy American, hire American" and that "every decision on trade, on taxes, on immigration, on foreign affairs, will be made to benefit American workers and American families" [6,7]. To this end, he has introduced a series of tax reform policies to give small and medium-sized enterprises tax relief while prompting multinational companies to invest back home, increasing jobs. On the issue of immigration, Trump argues that open borders have led to an increase in drugs and violence, while cheap labour has taken positions away from Americans. At the same time, the large number of illegal immigrants has put too much pressure on the education and healthcare systems [2]. As a result, he signed two executive orders, "Border Security and Immigration Enforcement Improvements" and "Enhancing Public Safety in the Interior of the United States", to tighten immigration policies and build the US-Mexico wall at the beginning of his term [8,9]. In addition, Trump has banned people from seven countries in the Middle East and Africa from entering the US by signing a series of travel bans. Meanwhile, Teng and Luo also argue that Trump's emphasis on American identity has manifested itself internally by emphasizing the high degree of purity of ethnic, religious and political groups. Trump exploits the identity anxiety of the population, significantly lower and middle-class whites, to hype populism and wins support for the vote [10].

Downplaying the Leader of the Liberal International Order and Reducing Global Responsibilities
According to the 2017 US National Security Strategy, the Trump administration believes that the US is facing many security and economic challenges and that its limited involvement in international affairs should address local challenges without excessive overseas obligations, which should be . This is most directly reflected in Trump's "exit diplomacy", as he has stated that his doctrine is Americanism rather than globalism. Since he took office, the US has withdrawn from international organizations and multilateral treaties such as the TPP, The Paris Agreement, UNESCO, The Iranian Nuclear Deal, United Nations Human Rights Council, INF Treaty, WHO and others. According to Sun and Sheng, these actions indicate that Trump is trying to reduce alliance, global governance, and international moral responsibilities. He argues that allies are the cornerstone of the free international order constructed by the US. Still, the Trump administration emphasizes the unfair treatment the US has experienced in its alliances and wants allies to take on more obligations and roles. For example, it has demanded that NATO and Japan and South Korea allies be able to take on more responsibility for defence [12]. This is echoed by Kupchan, who points out that Trump advocates strategic contraction, blames allies for not spending enough on defence and wants Europe to increase its ability to defend itself [13]. And this hostile attitude towards NATO would undoubtedly threaten the unity of the transatlantic alliance.

Focusing on Inward-looking Industrial Policy and Protecting the Development of Domestic Trade
First, Trump focuses on "inward-looking," i.e. localism. He believes globalization has made US manufacturing uncompetitive and that it needs to be revamped to drive economic growth, and he advocates the return of manufacturing and the cultivation of an independent and complete industrial chain in the US. In December 2017, Trump signed a tax reform bill that reduced the corporate income tax from a progressive 35% to a single rate of 21% [14]. This will make US-based companies more competitive and less likely to relocate out of the country. In addition, overseas profits of US multinationals will not be taxed in the US, thereby facilitating the repatriation of capital. He has also eased restrictions on energy companies by removing emissions regulations for coal-fired power plants.
He has boosted employment and reduced dependence on imported oil by promoting energy extraction. At the same time, Trump has expanded spending on infrastructure investment and financial deregulation to stimulate domestic economic growth and increase job creation.
In addition, at the international level, Trump has protected the interests of domestic companies by imposing anti-dumping and countervailing duties, imposing retaliatory tariffs and withdrawing bilateral trade preferences. According to Steil and Rocca, Trump has imposed a 25% tariff on almost all foreign steel imports in anticipation of reducing unfair trade competition and restructuring the US steel industry [15]. In addition, Trump sees poor trade agreements as the culprit for deepening unemployment and trade deficits. He has reacted lukewarmly to multilateral trade mechanisms and returned to bilateral negotiations to reduce constraints. Examples include his choice to withdraw from The Trans-Pacific Partnership (TPP) and his rejection of NAFTA. He has promoted the development of overseas markets and the export of local products through trade agreements with South Korea, Canada and Mexico [16].
Trump has taken a much stricter stance regarding his policy towards China. In the area of tariffs, high tariffs have been imposed on a large number of Chinese goods. In the area of investment, the signing of the Foreign Investment Risk Review Modernization Act of 2018 has imposed stricter restrictions on Chinese companies investing in the US and acquiring US companies. In the technology sector, the Trump administration has restricted the exchange of students and technicians between China and the US and imposed a technology embargo and blockade on Chinese companies. US-China technology cooperation has been hit hard. Trump's aggressive policies toward China have pushed for an economic decoupling between the US and China. He has tweeted, "We don't need China and, frankly, would be far better off without them..." [17]. And in an interview with Fox News, he said that in the face of the Chinese threat, "we could cut the whole relationship" [18]. As Hirsh states, Trump's real goal before he became president was to decouple the US from China [19]. And this is supported by Johnson and Gramer, who argue that the harsh measures taken by the US in areas such as technology, tariffs and supply chains are designed to divide two of the world's largest economies [20]. A similar view is held by Barboza and Bader. They argue that US-China relations have been severely damaged in the four years of Trump's administration and that the US is moving towards complete decoupling in some areas [21].
However, it is also important to note that some scholars do not see Trump as a return to traditional isolationism. For example, Xiao argues that the US withdrawal from diplomacy is not a sign of isolationism, as the US has maintained and even grown its security partnerships with other countries and regions [22]. Jiao also argues that Trump has pursued a conservative internationalist strategy since taking office. He advocates a leading role for the US in international affairs. Still, he emphasizes the importance of force as an instrument of foreign policy and the need to establish a balance of power pattern in favour of the US. He believes that the US alliance system and foreign interventionism have remained intact during Trump's presidency [23]. For example, Trump launched a military strike on Syria soon after taking office. In his speech in Warsaw, he showed his intention to defend Western civilization, among other things.

Reasons for Trump's Return to Isolationism
First, the relative decline of US manufacturing has become an essential source of the revival of isolationism. Since economic globalization, the transnational flow of capital and the interconnection of enterprises from different countries have developed rapidly. Multinational companies have globalized the production process of their products following the energy advantages, policy environment and production characteristics of other countries, forming global value chains. The impact of international trade and technological advances have stimulated industrial and demographic shifts in the United States, which in turn have further led to the decline of traditional industrial areas such as those in the Northeast. The external change in employment and deterioration in income distribution that occurred as a result of this has led to a decline in the standard of living of the general population. According to Song, the size of the US middle class has tended to shrink, particularly in the aftermath of the financial crisis. Its population share fell from 62% in 1970 to 43% in 2015. In terms of income, the median household income in the US has been declining since the onset of the financial crisis until 2015, when it saw its first annual increase. However, it is still 1.6% below the 2007 level [24]. The decline in the middle class has widened the gap between the rich and the poor in society while providing a breeding ground for anti-globalization thinking and even populism. As Sun and Seng argue, globalization has impacted vulnerable social groups within the US that lack competitiveness. Silver et al. hold a similar view, arguing that globalization has made limited employment opportunities, unfair competition between small businesses and retail chains and large multinational corporations threaten the identity of local communities [25]. At the same time, the accumulation of companies across the border also attracts large inflows of people and capital, putting upward pressure on the cost of living for residents. These globalized disillusioned have gradually opposed free trade and advocated protectionist measures to create barriers for potential competitors to enter the US market. Moreover, Trump himself has promoted isolationism. Trump's business experience has given him a mercantilist and unilateralist streak. This is reflected in foreign policy in the importance of commercial interests. The Trump administration emphasizes principled realism and attempts to construct an order of checks and balances of power and excellent power coordination based on the principle of energy, with a commercial undertone characterized by transactions. For example, in dealing with the US in its relations with mainland China and Taiwan, Trump wants to counterbalance mainland China by enhancing ties with Taiwan. Playing the "Taiwan card" has become a distinctive feature of Trump's policy towards Taiwan in exchange for concessions from mainland China in certain areas [26]. In addition, Trump's withdrawal from the Paris Agreement on the grounds of a fair agreement and the imposition of taxes on Chinese goods reflect his transactional approach to promoting isolationism. According to Song, Trump has used the international community's fear of US unilateralism and the resulting potential for de-globalisation to increase his leverage in economic and trade negotiations with other countries [27]. At the same time, his campaign focused more on the disillusioned and victims of globalisation, arguing that foreign policy should serve domestic development goals and appealing to the isolationist tendencies of the electorate. He must put this position into practise to deliver on his promises once in power.
In addition, isolationism is a reflection of the strategic contraction of the US, which is often a reflection of the international environment and fluctuations in relative power. The financial crisis of 2008 took its toll on the economic strength of the US, while the rapid development of emerging economies such as China has challenged the international position and influence of the US. For example, China's GDP share of US GDP has risen from around 20% in 2007 to 67% in 2018 [28]. In addition, the overseas military operations of the Bush and Obama administrations have generated significant military spending and casualties. They have also caused the federal government's debt ratio to rise rapidly. These issues have led to growing public scepticism about the results of US involvement in international affairs. According to pew research, in 2016, most Americans wanted the US to focus more on domestic affairs and leave other countries to deal with their problems [29]. Against a backdrop of shocks to the relative power of the US, the US has adopted varying degrees of strategic contraction since the Obama administration. For example, Obama's "don't do anything stupid" and "strategic patience" approach to diplomacy. After Trump took office, with his isolationist tendencies, this philosophy became the right thing to do in line with the strategic contraction [30]. For example, in contrast to Obama's expansion of the alliance system in the Asia-Pacific region, Trump has pressured his allies to return to and adjust bilateral economic relations to reduce their trade surpluses with the US.

Conclusion
In conclusion, considering the loss of manufacturing in the United States due to globalization and the financial crisis, the traditional industrial areas of the United States have seen a decline. And the people's standard of living has declined due to shifts in employment and reduced incomes. These victims of globalization are opposed to free trade and want the US to focus more on internal matters. In addition, the relative decline of US global influence and power, the resulting strategic contraction, and Trump's mercantilist character are driving an return to an isolationist diplomatic line. For example, Trump's focus on America First, his indifference to American allies and its responsibility as a leader of the liberal international order, and the protectionist industrial policy. This paper systematically analyses the manifestations of isolationism and its causes in the Trump era. However, the study does not analyse insularity's domestic and global impact on the US. It is suggested that future researchers examine how the Trump legacy with its isolationist character has worked its way into the Biden administration.