The information required to build one is already available - albiet not a highly optimized one. How to refine uranium, the design, etc. You can even buy uranium

The information required to build one is already available - albiet not a highly optimized one. How to refine uranium, the design, etc. You can even buy uranium on amazon legally. The main barrier to entry for them is the massive amount of refinement required to make any useful amount of the required materials, like multiple warehouses size operation. --- The big difference here is stable diffusion has shown you can train a highly capable model under 1 million dollars. LLaMa is making some interesting advances as well (finetuning a LOrA takes ~3 hours on a 4090). Training/finetuning/inference capable AI is quickly becoming more feasible (albiet trailing the commercial stuff) for the average consumer hardware.