Shipments of the magnets, essential for assembling everything from cars and drones to robots and missiles, have been halted at many Chinese ports while the Chinese government drafts a new regulatory system. Once in place, the new system could permanently prevent supplies from reaching certain companies, including American military contractors.
Pretty vital stuff for future Jets, advanced radars, missiles etc on just the military side. Strategic move by China it will probably slow the US down a lot in a great many areas for potentially years.