The largest particle accelerator in existence, the LHC, is shown below, compared to the planned Future Circular Collider. Obviously the LHC is not enough to get the job done and they need a bigger one.
https://preview.redd.it/8z0f3kdvzhu81.jpg?width=370&format=pjpg&auto=webp&s=f843a6d18b0baa0f4346d0040266247ebfe7791a