U.S. tariff measures have expanded beyond China to include a broad range of major trading partners, such as the European Union, Japan, India, and Brazil. The global spread of tariff barriers poses a significant risk to the Korean economy, which has developed within an open, multilateral trading system. This study aims to support the sustainable growth of Korean trade by providing policy and strategic guidance in response to the global spread of tariff barriers. To this end, the study conducts a historical review of tariff increases, an examination of relevant trade law, empirical analyses, and simulation analyses based on a trade model.

Chapter 1 reviews the historical evolution of tariff policy across the 1930s, the 1970s, and the post-WTO period. Chapter 2 provides a comprehensive review of the expansion of U.S.-originated tariff measures, their legal foundations, and the responses of major economies. Chapter 3 traces the channels through which tariff increases affect the economy by reviewing the existing literature, and highlights theoretical, empirical, and quantitative findings on how tariff hikes influence prices, trade diversion, investment, employment, and welfare. Chapter 4 provides a statistical assessment of changes in the trade structures of major countries following the first Trump administration and examines performance trends among Korean firms exporting to the U.S. Chapter 5 develops a dynamic trade model to quantify how different global tariff scenarios influence trade flows, prices, and welfare.

The main findings are as follows. First, in the U.S. import market, China’s share has declined, while the shares of Korea, Mexico, Vietnam, and other countries have increased. Korea’s exports to the United States have grown, particularly in core industries. At the firm level, however, a dual pattern emerges: sales have increased, but profitability has not improved.

Second, the dynamic trade model shows that rising tariff barriers and policy uncertainty have differentiated effects depending on each country’s industrial structure and the substitutability of goods. Overall, however, they tend to result in lower trade, higher prices, and reduced consumer welfare. This underscores the need to mitigate short-term disruptions while strengthening medium- to long-term fundamentals. Our scenario analysis further indicates that the primary driver of global trade contraction is not targeted high tariffs on specific products but the escalation of tariff barriers between the U.S. and China. In addition, countries that, through separate agreements, secured reductions in reciprocal tariff rates and Section 232 tariffs experienced relatively smaller adverse effects, as they gained a relative price advantage over countries that did not.

Third, the current global trade environment is characterized by the weakening enforcement of WTO-based multilateral rules and the growing prominence of a power-based approach, led by the United States, that relies on domestic law as a policy instrument. In response, major economies are pursuing a range of policy options—including WTO litigation, retaliatory tariffs, negotiations, and the strengthening of domestic industrial protection mechanisms—depending on the level of tariff pressure under the second Trump administration and their respective economic structures.

Finally, Chapter 6 reviews Korea’s policy responses under the first Trump administration and the Biden administration. Building on the main findings of Chapters 1 through 5, it sets out six policy directions for the Korean government and businesses to prepare for the possible persistence and entrenchment of tariff barriers: (1) managing the “dual risks” confronting Korea’s exports; (2) pursuing product- and measure- specific responses while strategically utilizing exception clauses; (3) minimizing the adverse effects of circumvention trade and making effective use of trade remedy mechanisms; (4) expanding support for firms affected by global trade disruptions; (5) strengthening coordination between industrial policy and trade policy; and (6) making strategic use of legal and diplomatic channels.

국문요약

제1장 서론
1. 연구 배경과 목적
2. 주요 연구 내용
3. 글로벌 관세장벽의 역사적 배경

제2장 글로벌 관세장벽의 확산 동향
1. 미국발 관세 조치의 확산 배경
2. 미국발 관세장벽의 확산
3. 주요국의 대응
4. 소결

제3장 글로벌 관세장벽 확산에 관한 선행연구
1. 개요
2. 관세의 파급 경로: 큰 그림
3. 경제에 미치는 영향

제4장 미국발 관세장벽 확산이 미친 영향
1. 주요국의 무역 구조 변화
2. 무역에 미친 영향에 대한 실증분석
3. 우리나라 대미국 수출기업의 성과 동향
4. 소결

제5장 관세장벽 확산과 향후 무역 및 경제 변화
1. 개요
2. 분석 모형
3. 무역 불확실성의 무역비용 추정
4. 분석 시나리오 및 데이터
5. 분석 결과
6. 소결

제6장 결론
1. 한국의 과거 대응
2. 향후 전망과 대응 방향

참고문헌

부록

Executive Summary