In September, the US commerce department launched an investigation into the national security impact of imports of neodymium-iron-boron (NdFeB) permanent magnets, the most widely manufactured rare earth magnet. Governments, businesses, and experts submitted public comments to weigh in on whether the US should slap tariffs on imports of NdFeB magnets as a way of counteracting the security risks of being overly reliant on imports from foreign countries, especially China. Under Section 232 of the Trade Expansion Act, the president can impose tariffs on products that the commerce department deems to be imported “in such quantities or under such circumstances as to threaten to impair the national security.” Among the comments submitted by the Nov. 12 deadline, the European Union came out most strongly in opposition to any kind of US tariffs on NdFeB magnets, which have a broad range of military and civilian industrial uses.