This study examines the evolutionary process of protectionism in international trade from Antiquity to the present day. While the ontological necessity of trade and specialization are explained through the views of Plato and Aristotle, the transition from mercantilist zero-sum trade to the liberal views based on mutual gain by Smith and Ricardo is analyzed. The principle of reciprocity in tariffs, which prevailed from 1934 to 2018, has given way to the principle of restriction in tariffs following the China Shock triggered by China’s accession to the World Trade Organization (WTO) in 2001 and the USA’s subsequent shift towards strategic protectionism. China’s emergence as a major actor in global production, trade, and technology, combined with the record US-China trade deficit reaching $418 billion in 2018 and domestic economic pressures in the US, have steered the US towards protectionist policies. Since deep Global Value Chains (GVC), established through modern transportation and communication technologies, have made countries interdependent, this tension between the US and China negatively affects global efficiency and production through a multiplier effect. The trade war causes the postponement of investment decisions, rising costs, declining efficiency, and a significant reduction in global welfare by increasing Trade Policy Uncertainty (TPU). The new tariffs implemented in 2025 indicate that these protectionist measures and the climate of uncertainty suppressing investments will evolve into a permanent structural element of the global economy.