Trade Policy Reversion: Quantifying the Diversionary Impact of Non-Tariff Barriers on Bilateral Trade Flows (2015–2024)

ENG: In recent years, protectionism has become a hallmark of the global economy and international trade. This study quantifies the measurable impact of tariff and non-tariff barriers on bilateral trade flows among 30 major economies from 2015 to 2024. Employing a panel data gravity model, the paper specifies the logarithm of bilateral trade flows as the dependent variable, with average tariff rates and a non-tariff measures (NTM) index as key explanatory variables, while controlling for GDP, exchange rate volatility, distance, and trade agreements. Estimations are performed using fixed-effects and instrumental-variable approaches to address potential endogeneity and unobserved heterogeneity. The empirical results reveal that a one-percentage-point increase in tariffs reduces bilateral trade flows by 0.12%, while a 0.1-point rise in the NTM index lowers trade by 3.5%, confirming the diversionary effects of modern protectionism. The findings demonstrate that regulatory protectionism exerts stronger trade-restrictive effects than traditional tariffs, particularly in technology-intensive sectors. Policymakers are urged to design adaptive trade strategies that preserve national competitiveness while maintaining open global trade channels to ensure sustainable growth.