The Smoot-Hawley Tariff Act (signed 1930-06-1…

World trade fell roughly 65% in nominal terms 1929- 1933 vs roughly 50% nominal-GDP fall. The descriptive claim is long-history Maddison/PWT-grounded that the 1930-1933 period shows the largest peacetime trade-collapse in 20th-century history, with retaliatory tariff cascades documented in the trade-policy literature.

Pre-registration

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first-spec commit 4c8ce8e · 2026-07-18T22:11:21Z

run generated · 2026-04-30T08:07:40Z

Run timestamp predates this path's first git-add commit (rebase, rename, or pre-git local run). Spec hash is still the path's first-add commit — not repository HEAD — but ordering is not a clean pre-registration proof.

The Smoot-Hawley Tariff Act (signed 1930-06-17, raising US weighted average tariffs on dutiable imports from approximately 40% to approximately 47-50%) coincided with a collapse in global merchandise trade that exceeded the contemporaneous fall in global GDP. World trade fell roughly 65% in nominal terms 1929- 1933 vs roughly 50% nominal-GDP fall. The descriptive claim is long-history Maddison/PWT-grounded that the 1930-1933 period shows the largest peacetime trade-collapse in 20th-century history, with retaliatory tariff cascades documented in the trade-policy literature.

Falsification criterion — what would disprove this

set before the run · honoured after

This hypothesis is considered falsified if:

SUPPORTED if trade-to-GDP for the major-economy panel mean fell from 1925-1929 mean to 1932-1933 mean by >=8 pp (a collapse exceeding any other peacetime episode in JST coverage). REFUTED if the fall was less than 5 pp.

formal test & threshold

test:      descriptive_smoot_hawley_great_depression_trade_collapse
threshold: PRIMARY: panel-mean trade-to-GDP fall(1925-29 -> 1932-33) >= 8 pp. METHOD_VALID: JST trade-to-GDP series available for >=8 of the panel countries 1925-1933.

Method

Template: descriptive
Clustering: none
Sample: 14 countries · 1925 – 1939
Evidence type: descriptive

Long-history descriptive analysis using JST and Maddison/PWT data. Reports trade-to-GDP collapse magnitude across major economies 1929-1933 vs 1925-1929 baseline. Identification at the international-tariff-cascade level is qualitative and historiographic; this spec records the magnitude pattern.

Data

Variable	Source	Transform
real_gdp_pc_pwt outcome	pwt:rgdpetier 3 maddison:gdppc_ppptier 3	log
trade_to_gdp_jst outcome	jst:exports_to_gdptier 3 jst:imports_to_gdptier 3	level

● ready · ● pending · ● reconstruct-needed

Strongest opposing argument

Every hypothesis ships with its charitable opposing argument. The framework earns credibility by handling objections at their strongest, not weakest.

The Smoot-Hawley Tariff Act (signed 1930-06-17, raising US weighted average tariffs on dutiable imports from approximately 40% to approximately 47-50%) coincided with a collapse in global merchandise trade that exceeded the contemporaneous fall in global GDP.

In ordinary language