AI is blocked two ways: companies geo-fence the chatbots, states censor the model hub
'AI is blocked in Iran, Russia, China' is one headline hiding two different stories with two different villains. Tag WHY each AI service is unreachable and a clean division of labor appears: the AI COMPANIES geo-fence their consumer CHATBOTS out of sanctioned countries, while the STATES network-censor the developer SUPPLY CHAIN (the open model+dataset hub). The blocked pairs split almost evenly — ~20 vendor geo-restrictions and ~20 state network blocks — but on different layers. Vendor geo-restriction: ChatGPT/Claude/Gemini/Perplexity unreachable in Iran, Russia, Cuba, Belarus, Syria, Venezuela because OpenAI/Anthropic/Google/Perplexity decline those markets (US sanctions/export-control); the network path is open, the vendor turns the user away, the firewall isn't involved. State network censorship: DOMINATED by HuggingFace, network-blocked in 16 countries (AE/AZ/BY/CN/CU/EG/IQ/IR/KZ/MM/PK/RU/SA/SY/VE/VN) — their filtering drops the connection to the model/dataset hub — plus China network-blocking a few chatbots (ChatGPT, Gemini, Mistral, Perplexity). So an Iranian dev can't open ChatGPT (OpenAI won't serve Iran) AND can't reach HuggingFace (Iran blocks it) — same person, two tools, two entirely different gatekeepers. The single most-blocked AI service is HuggingFace (16 countries, more than ChatGPT's 7 or Claude's 8): censorship of AI is increasingly censorship of the supply chain, not just the chat apps. China is the full-stack censor (6 services: firewall on ChatGPT/Gemini/Mistral/Perplexity/HuggingFace, Claude vendor-geo). Heavy general censors Ethiopia/Sudan/Uzbekistan leave AI alone. The matrix tags the mechanism per cell; the summary ships a blocked_by breakdown (vendor_geo_restriction vs state_network_block). Live: /v1/atlas/ai-availability. (Correction: an earlier version put state-censorship at 4 and framed it 'mostly vendor-geo' — a miscount over a stale snapshot that omitted the 16 HuggingFace blocks; the live split is ~20/20.)