Section 232 tariffs

Section 232 of the Trade Expansion Act of 1962 authorizes the president to adjust imports of a product if the Commerce Department finds, after an investigation, that the imports threaten to impair national security. The president may use tariffs, quotas or other measures, and Congress has no formal role in approving them.

The authority was seldom used until 2018, when President Trump imposed tariffs of 25 percent on steel and 10 percent on aluminum from many countries, citing national security, and later extended it to other products. Commerce investigations since then have covered autos, copper, semiconductors and other products. The Biden administration kept many of the tariffs while negotiating quotas with some partners, and in 2025 the Trump administration expanded their use.

Defenders say the statute lets the president protect critical industries and supply chains, particularly steel for defense. Critics argue that "national security" has been interpreted too broadly, shielding protectionist measures from congressional oversight and inviting retaliation, and that the delegation of tariff power from Congress, which holds the power to lay duties under Article I, raises nondelegation doctrine concerns. Courts have deferred to the executive: the Supreme Court upheld broad discretion in Federal Energy Administration v. Algonquin SNG (1976). See tariff.