American campus speech codes and informal speech norms discriminate against foreign students and faculty, and that’s an important but neglected reason why they should be challenged. Speech codes often claim to protect ‘cultural diversity’ on campuses, but they often do the reverse. They impose narrow American norms of political correctness on foreign grad students, post-docs, and faculty who can’t realistically understand what Americans will find offensive. From neurodiversity to cultural diversity In an article for Quillette last year, I argued that campus speech codes discriminate against ‘neurodivergent’ people who have Asperger’s syndrome, bipolar disorder, PTSD, ADHD, or other conditions. These disorders make it hard to understand and follow speech codes that prohibit saying or doing anything that others might find offensive. In a follow-up article, I outlined how neurodivergent people could use the Americans with Disabilities Act to challenge such discriminatory speech codes. These neurodivergent conditions are all heritable, and they make people’s brains different from the ‘neurotypical’ average brain, so they could be called ‘genetic neurodiversity’. But beyond genetic neurodiversity, there’s ‘cultural neurodiversity’: different …