Donald Trump’s second-term trade agenda has revived a crude but potent instrument: tariffs. In the space of four months — January to April 2025 — the average levy on imported goods rocketed from 2.5 percent to roughly 27 percent, the steepest hike (and highest level) since the 1920s. Struggling to slot this shock into a tidy narrative, analysts at the Council on Foreign Relations, The National Interest, and Fortune have dusted off an old label — import-substitution industrialization (ISI). The analogy is neat; it is also wrong. Trump’s program is not the heir to mid-century Latin American development strategy. It is improvised protectionism without the architecture that once made ISI, for all its contentions, a coherent policy; to claim otherwise is a categorical error that inadvertently glazes Trump’s economic credibility, even though the former head of the Federal Reserve has said he “doesn’t understand economic policy.”