What does a beautiful 25-year-old woman need for a night out in Dublin? It goes on top of the glassy make-up, which is applied with precision and care. It sits over the white cropped top and freshly pressed jeans, judiciously chosen and coordinated. And it’s heavier than the buttery brown leather handbag sitting on her shoulder. It’s the weighty armour of vigilance that almost all women wear without thinking whenever they leave the house.