I wear clogs and jeans, usually not even a jacket. I carry a small rucksack and put whatever I need in there (ie reading material and snacks). You can't take water through security any more ( I guess it might detonate?) and I just put my belt and wallet in my rucksack when going through security.
Granted it seems extreme to search every pleat in a kilt, but consider what would happen if security was relaxed. It's a sad world we live in and these are the side effects we must learn to live with.