2018年初，特朗普總統宣布對企業和個人實行大規模減稅政策，企業所得稅從35%大幅下調到21%，個人所得稅也不同程度低下調，其中富人和中產階級收益良多。再加上他上台後兌現承諾，陸續放鬆了對華爾街金融機構的監管，這兩大措施有力促進了企業投資和個人消費，美國GDP增長從當年第二季度開始加快，第一季度GDP增長2.2%，第二季度猛增到4.2%，第三季度增長3.5%，第四季度微增2.2%，經濟出現了強勁復蘇。2018年美國GDP增長2.9%，超過了2017年的2.3%，是自2007年發生次貸危機12年以來增長最快的一年。因此，特朗普總統在2018年秋季聯合國大會上得意忘形地自我吹噓說，他是“美國歷史上最偉大的總統”，被世界輿論嘲笑。

但是，美國經濟從2019年第二季度開始步入下行軌道。特朗普大規模減稅（規模達1.5萬億美元）刺激經濟的效應僅延續到2019年第一季度。第一季度GDP增長3.1%，而第二季度增長2.0%，呈現明顯的下滑，第三季度僅增長1.9%。

美聯儲、美國全國商業經濟學會和世界主要經濟機構均預測今明兩年美國經濟處於下行軌道。2019年9月18日，美聯儲預測美國經濟2019年僅增長2.2%，2020年增長2.0%。10月7日，美國全國商業經濟學會預測美國經濟2019年增長2.3%，2020年增長1.8%。

2019年6月4日，世界銀行預測美國經濟2019年增長2.5%，2020年增長1.7%，2021年增長1.6%。9月19日，IMF預測美國經濟2019年增長2.4%，2020年增長2.0%。10月15日，經合組織也做出與IMF相同的預測。

首先，急劇增長的財政赤字和沉重的國債負擔給美國經濟發展造成了巨大的壓力。

特朗普入主白宮後，大搞赤字財政，致使政府的財政赤字急劇增加。2017財年赤字6660億美元，佔GDP的3.5%。2018財年赤字7790億美元，佔GDP的3.9%。2019財年赤字達9844億美元，佔GDP的4.6%，財政赤字同比增長26%。特朗普執政後三個財年累計財政赤字達24294億美元。

與此同時，美國國債急劇增加。特朗普入主白宮時，國債為19.97萬億美元，2019年11月19日達到23.054萬億美元，人均7.12萬美元, 摺合人民幣50萬元。特朗普擔任總統兩年十個月國債增加了3.084萬億美元，年均1.17萬億美元。巨額國債必然帶來沉重的償息負擔，現在美國政府每天要支付10億美元的債務利息，未來十年需要支付的債務利息將達到7萬億美元。

其次，特朗普大打貿易戰也拖累了美國經濟的發展。

2019年11月13日，美國消費者新聞頻道網站報道的海運數據顯示，特朗普對華貿易戰給美國造成的損失將永遠無法彌補。“從洛杉磯這個繁忙港口運往中國的美國貨物量已連續12月下降。2019年10月經該港的出口額同比下降了19.1%。中國對美國商品加征的報復性關稅影響了96.6%經洛杉磯港運輸的美國對華出口商品，總價值達到199億美元”。“美國遭受的損失是長期的，而且是多方面的。這場貿易戰已經給美國農業造成110億美元的損失，且受影響的行業不僅限於此”。“在貿易戰爆發前美國出口的液化天然氣有4.3%賣給了中國，如果按滾動市營統計中國在美國液化天然氣出口中的佔比高達16%。但2019年8月中國在美國液化天然氣出口中的佔比大幅降至1%。在美國原油出口中的佔比也從2018年1月的20%降至2019年8月的僅1.2%。”“另外，據美國全國零食商聯合會公布的數據，從2018年2月貿易戰開始到2019年9月，美國消費者和商家已額外支付了380億美元。”

從大豆出口看，2017年美國對中國出口大豆3285萬噸，價值140億美元，占當年美國大豆出口的65%。而2018年美國對華出口大豆1664萬噸，降幅達49%。

利用高新技術打壓中國，破壞了國際產業鏈，結果也傷害了美國的高新技術大企業，造成兩敗俱傷。2018年4月16日，特朗普宣布對中國第二大通訊企業中興採取制裁措施，停止芯片供應七年。次日美國著名高新技術公司高通和英特爾的股票大跌9%，第三日高通宣布裁員1500人，第四日高通、英特爾和美光的CEO聯合到白宮請願，請求撤銷對中興的制裁，否則三大公司總額10億美元的芯片無法處理。特朗普總統這才意識到制裁大棒打在中興的身上，也疼在高通、英特爾和美光等企業的心上。後經談判妥協，原定停止芯片供應七年的計劃只執行了一個月零14天，於6月1日恢復芯片的供應。

今年5月16日，特朗普宣布對對中國企業華為實行全面制裁，停止所有零部件的供應。誰知次日，高通、英特爾、美光、博通、賽思靈、偉創力、英偉達甚至谷歌和微軟等11家美國高新技術的CEO聯合到白宮請願，請求允許它們將華為訂購的高達110億美元的通訊器材發貨給華為，否則11家公司將面臨巨額損失。在大型高新技術企業的巨大壓力下，特朗普總統於5月19日深夜（星期天）宣布給制裁華為提供三個月豁免期，執行日期推至8月19日。在美國企業的努力之下，8月19日美國商務部長羅斯宣布繼續延長三個月的豁免期到11月19日。11月18日，商務部長羅斯宣布再次延長豁免期三個月，將對華為的制載推遲到2020年2月16日。

華為事件充分說明，在經濟全球化的世界上，任何一個國家不可能在不承受損失的情況下去制裁與產業鏈相關的另外一個國家的相關企業。這也再次說明發動貿易戰必然是兩敗俱傷，不可能是一方佔便宜，而另一方完全吃虧，因為國際經貿歷來是互惠互利合作共贏的。

第三，2017-2018年美國吸引外資出現大幅下降，影響美國經濟的發展。

據聯合國貿發組織的統計，奧巴馬政府最後兩年美國吸引外資大幅度增加，2015年吸引外資4676億美元，2016年為4718億美元。而特朗普入主白宮後，吸引外資的形勢發生了逆轉，2017年吸引外資2772億美元，同比大跌41%，2018年降至2518億美元，同比下跌9.0%。眾所周知，美國是具有世界規模的經濟體，它的發展需要大規模世界資金來支撐，而且這也有利於美元的國際貨幣地位。因此，美國近兩年吸引外資大幅下降，對美國經濟來講絕非好消息。

現在，離2020年11月3日的大選還有不到一年時間了。面對美國經濟繼續下滑，特朗普總統除了繼續施壓美聯儲降息擴表外，沒有更有效的對策。2019年年中，特朗普總統提出減稅2.0版方案，即給中產階級年收入高於13.6萬美元的人減免所得稅，給企業的盈利減稅，藉以刺激消費和企業投資，進而防止經濟下滑。但白宮的顧問們對他說，減稅方案在民主黨掌控的眾議院很難通過，因為民主黨為明年大選準備的炮彈之一就是財政赤字猛增和巨額國債。民主黨候選人的政策主張是加稅，特別是給富人加稅，這也是民主黨的傳統理念。還有一個辦法可以起到立竿見影的作用，就是儘快停止與中國、歐盟等的貿易戰，取消額外加征的高關稅，這對美國經濟的增長和減輕廣大消費者的負擔進而刺激美國國內消費大有好處。

特朗普總統發動貿易戰的初衷是大規模減少美國的貿易逆差，事實證明這個目的根本達不到。據美國商務部統計，2018年美國貨物貿易逆差高達8787億美元，同比增長10.4%。美國與102個國家都存在貿易逆差，這難道也怪中國或者歐盟嗎？

為了贏得大選，2020年美國經濟必須止跌回升，特別是臨近大選的下半年，美國經濟增長必須高於2019年的增幅。美國歷史表明，大選之年經濟表現如何將發揮決定性作用。1992年大選，老布殊總統就敗在經濟下滑的形勢之下，這個教訓值得拚命想連任的特朗普總統汲取。

In early 2018, United States President Donald Trump announced generous tax cuts for American companies and individuals. The corporate tax rate was lowered to 21 percent from a high of 35 percent, and individual income tax rates were also reduced, with the wealthy and middle class as the biggest beneficiaries. In addition, as part of his efforts to keep his election promises, Trump relaxed regulations on Wall Street financial institutions. All these measures gave a strong boost to business investment and personal consumption expenditures.Meanwhile, American GDP growth accelerated in the second quarter of 2018. Specifically, the economy grew by 2.2, 4.2, 3.5 and 2.2 percent in 2018 on a quarterly basis, pointing to strong signs of recovery. Overall, GDP increased by 2.9 percent in 2018, notably higher than in 2017 (2.3 percent) and the highest in the 12 years since the 2007 subprime mortgage crisis. That may explain why in the United Nations General Assembly in the fall of 2018, President Trump claimed that “my administration has accomplished more than almost any administration in the history of our country,” which became a matter of derision worldwide.

The effect of the massive tax cuts, which amounted to $1.5 trillion dollars, lasted until the first quarter of 2019. Then the American economy continued a downward trend: GDP growth eased from 3.1 percent in Q1 to 2.0 percent in Q2 and then to 1.9 percent in Q3.

In addition, the Federal Reserve, National Association for Business Economics and major international economic organizations predicted a continued American economic slowdown for 2019 and 2020. On Sept. 18, 2019, the Fed expected the economy to grow 2.2 percent in 2019 and 2.0 percent in 2020. On Nov. 7, the National Association for Business Economics forecast that American GDP growth would slow to 2.3 percent in 2019 and then to 1.8 percent in 2020.

On June 4, the World Bank said U.S. growth would slow to 2.5 percent in 2019, and further slip to 1.7 percent in 2020 and 1.6 percent in 2021. On Sept. 19, the IMF projected modest 2.4 percent growth for the United States in 2019 and 2.0 percent in 2020. The OECD predictions released on Oct. 15 were in line with those of the IMF.

Surging fiscal deficit and enormous government debt impose a huge strain on economic growth.

Since taking office, Trump has been obsessed with deficit financing, thus dramatically expanding the fiscal deficit. In 2017 and 2018, the budget shortfall rose to $666 billion and then $779 billion, accounting respectively for 3.5 percent and 3.9 percent of GDP. In 2019, the deficit increased by 26 percent to $984.4 billion, or 4.6 percent of GDP. Taken together, the fiscal deficit incurred in the three years since Trump's inauguration adds up to $2.43 trillion.

Meanwhile, there has been a sharp increase in the U.S. national debt. The debt was $19.97 trillion when Trump became president, and the figure had risen to $23.05 trillion by Nov. 19, 2019, or $71,200 per capita. The new debt level reflects a rise of about $3.08 trillion in the 34 months, or $1.17 trillion annually, since Trump took office in 2017. The heavy national debt means heavy debt service pressure: the American government needs to pay out a total of $1 billion in interest every day, and its interest payments will total $7 trillion in the next decade.

Trump's China trade war holds back the American economy.

On Nov. 13, 2019, a CNBC article said that shipping data indicate that U.S. losses from Trump's China trade war will never be recovered.“U.S. exports to China from the bustling harbor of Los Angeles decreased for 12 consecutive months. It suffered a 19.1 percent drop in export volume from October 2018 to the same month in 2019. China's retaliatory tariffs hit 96.6 percent of the U.S. exports that passed through the L.A. port complex, with a price tag of $19.9 billion,” it said.“The list of losses is long and varied. The trade war has expanded beyond agriculture, which is $11 billion in the hole (and counting). … Before the trade war, U.S. LNG volume comprised 4.3 percent of Chinese imports, and China accounted for 16 percent trailing twelve-month basis (TTM) of U.S. LNG exports. In August 2019, China's LNG volume had slipped precipitously to 1 percent TTM. Crude oil has suffered a similar fate, accounting for 20 percent TTM of U.S. crude exports in January 2018 to just 1.2 percent TTM in August 2019.”In addition, it said: “According to the National Retail Federation, consumers and businesses have paid an additional $38 billion from the start of the trade war in February 2018 through September 2019.”

When it comes to soybean exports, America sold 32.85 million metric tons, or 65 percent of its global exports, to China in 2017 in deals worth $14 billion. This proportion shows that China may have difficulty finding a replacement for U.S. soybeans on the world market. But in 2018, American exports to China were just 16.64 million tons, down by 49 percent.

In the high-tech sector, America's crackdowns have disrupted the international industrial value chain and hurt its own high-tech companies as well. Simply put, they have led to a lose-lose situation. On April 16, 2018, the U.S. government announced sanctions on ZTE Corp., the second-largest telecom equipment maker in China, imposing a seven-year ban on purchases of crucial American technology, including chips. The next day, shares of American chipmakers Qualcomm and Intel fell by about 9 percent; on the third day, Qualcomm announced a layoff of 1,500 employees.On the fourth day, Qualcomm, Intel and Micron CEOs lobbied the White House to lift the ban because they could not figure out how to deal with their stockpile of chips worth $1 billion. Then President Trump came to realize that while the sanctions were targeted at ZTE, the effect was felt by American companies. After much negotiation, the U.S. government announced that it would permit chip exports to the Chinese company on June 1, effectively lifting the ban after one month and 14 days.

Then, on May 16, the Trump administration added China's Huawei Technologies to a trade blacklist, banning the company from buying parts and components from American companies without U.S. government approval. The next day, the chief executives of 11 American high-tech companies, including Quantum, Intel, Micron, Broadcom, Xilinx, Flextronics, Nvidia, Google and Microsoft, met with President Trump at the White House, asking for permission to supply their $11 billion worth of telecom equipment to the Chinese company to avoid huge financial losses.Under strong pressure from these tech giants, Trump made a late-night announcement on May 19 giving Huawei a three-month reprieve. This extension was supposed to end on Aug. 19, but an additional 90 days were announced by U.S. Commerce Secretary Wilbur Ross, thanks to the advocacy of American businesses. Three months later, on Nov. 18, Ross announced another three-month extension, moving the deadline to Feb. 16, 2020.

The Huawei saga reveals that in a globalized world, no single country can impose sanctions on foreign companies without causing losses to its own. Again, it proves that a trade war produces no winners. No one can win 100 percent, because international economic and trade cooperation is built on mutual benefit and win-win results.

A significant decrease in foreign investment between 2017 and 2018 also dragged down the U.S. economy.

According to the UNCTAD, in its last two years the Obama administration beefed up efforts to draw foreign investment, increasing inflows from $467.6 billion in 2015 to $471.8 billion in 2016. But things have taken a dramatic turn since Trump took office: The influx of foreign investment dropped to $277.2 billion in 2017, down by 41 percent year on year, and then dropped again to $251.8 billion in 2018, or 9.0 percent year on year.Simply put, there was a gap of $410.4 billion in the 2015-16 and 2017-18 periods.The state of the American economy has global implications. Development relies on massive foreign investment, which also contributes to the status of the dollar as the world's currency. Given this fact, a significant drop in foreign investment is definitely bad news for the American economy.

The next presidential election will take place on Nov. 3, 2020, which is less than a year away. In the face of the economic slowdown, President Trump seems to have no other effective measures at his disposal but to pressure the Fed to reduce interest rates and increase its balance sheet.In mid-2019, he introduced a tax-cut proposal dubbed Tax Cut 2.0. The goal was to reduce income tax for middle earners with an annual income of more than $136,000 and reduce business income tax rates to stimulate consumption and business investment, which ultimately was supposed to halt economic decline. But his advisers told him that it would be difficult to gain the approval of the House of Representatives, which is controlled by Democrats, because the surging fiscal deficit and national debt under Trump provides ammunition for the presidential election. After all, Democratic candidates traditionally argue for increased tax rates, especially for the rich.

For Trump, another solution that can produce immediate benefits is to end the trade war with China, as well as the dispute with the European Union and others, and to remove all extra tariffs. These moves would help grow the economy, reduce the financial burden on consumers and boost domestic consumption in the United States.In launching the trade war, President Trump originally hoped to dramatically reduce America's trade deficit, but it has been proved that this is a distant goal. According to the U.S. Department of Commerce, in 2018 the U.S. trade deficit in goods amounted to $878.7 billion, up by 10.4 percent year on year. And the country ran trade deficits with 102 countries. Is China or the European Union to blame for this problem?

To win the election, President Trump must figure out ways to halt an economic slide in 2020. More important, by the second half of 2020, he must ensure that the American economy will grow more robustly than it did in 2019.American history shows that economic performance in election years matters. George H.W. Bush, for example, lost his re-election bid in the 1992 presidential election because of an economic slowdown. This is a lesson that President Trump needs to learn from if he expects to secure another term.