Since his reelection, Trump has essentially launched a full-scale assault on the global trading system, terrorizing countries around the world with a seemingly endless barrage of tariffs and threats. The U.S. leader isn’t even pretending to abide by WTO rules anymore.

Moreover, his tariffs threaten to send the world back to the 1930s, when the spread of trade protectionism and beggar-thy-neighbor policies — spurred by America’s Smoot-Hawley Tariff Act — exacerbated the Great Depression.

Under these circumstances, allowing the U.S. to remain a member makes a mockery of the institution and its principles. And countries committed to preserving a rules-based trading order need to fight back and defend the system, punishing his blatant violation of WTO rules.

Today, the U.S. accounts for only about one-tenth of world trade. The global trade regime can survive without it — but only if the rest of the world continues to follow the rules. | Olivier Hoslet/EFE VIA EPA

The international legal order governing trade can only be sustained if countries face penalties for noncompliance. But by disabling the WTO Appellate Body, the U.S. has made it impossible to enforce global trade rules. Now, any country that loses a WTO dispute can block the ruling by simply filing an appeal to the defunct body. And by doing this in repeated disputes challenging its WTO-illegal policies, the U.S. has been able to break the rules with impunity.

In addition to the substantial harm caused by Trump’s policies, the broader danger here is that rule violation will spread, leading to the collapse of global trade. If his brazen rule-breaking goes unpunished, why should other countries abide by the rules?

Today, the U.S. accounts for only about one-tenth of world trade. The global trade regime can survive without it — but only if the rest of the world continues to follow the rules. It won’t, however, survive other countries imitating Trump’s rule-breaking, tariffs and other protectionist measures. This risk of contagion represents a grave threat to global economic security.