Nişantaşı Üniversitesi Sosyal Bilimler Dergisi

Öz

This study examines the impact of additional tariffs imposed by the Trump administration in 2018 on import volatility in the U.S. foreign trade. Imports from Mexico, China, Canada, and Germany, which are among the most significant trading partners of the U.S., have been analyzed within the framework of the automotive (Chapter 87), iron-steel (Chapter 73), and machinery (Chapter 84) sectors. Monthly import data for the period 2005-2024 have been used, and first differences of the series were taken, followed by the application of the EGARCH model for volatility analyses. The findings indicate that the tariffs implemented by the Trump administration had volatility-inducing and persistent effects, particularly on imports from Mexico and China. In contrast, imports from Canada and Germany exhibited relatively more stable volatility patterns. On a sectoral basis, the persistence of volatility shocks was found to be higher in automotive and machinery imports. Trump's potential re-election in 2025 and the introduction of new tariffs in the iron-steel and automotive sectors pose the risk of creating further uncertainties, especially in import processes with Mexico and China. The study's findings reveal that protectionist policies, such as tariffs, not only reduce import volumes but also negatively affect trade sustainability by causing long-term uncertainties in the market.