But DHS is not just security/law enforcement. There is a safety/response component there.
If you think that should be a seperate agency, all it's own, I'm down with that. Move CBP and ICE and other LE-related agencies over to DOJ, and leave the rest in DHS. You'd have to split the CG up too (cause they do more than LE). You could rename DHS to NRA (National Rescue Agency).