Motorists should be publicly encouraged to switch off car engines when the car is standing still. There should also be a public awareness campaign encouraging motorists to slow down in residential neighborhoods, and to watch out for pedestrians and bicyclists. Raising public awareness of bicycle safety is a good idea, but helmets are not the only factor in bicycle safety. It's important to emphasize that the main threat to bicyclists is cars, and the main life-preserving strategy is visibility. This involves lights, back flashers, and reflective tape on bicycles.
Helmets can be useful, too.
But most of the world doesn't use them, and foreign cyclists do not die like flies in bicycle crashes. Give away free helmets, by all means, but repeal the law. Don't subject bicyclists to measures that you would not even consider imposing on motorists. It just discourages bicycle use and encourages car use. When roads are opened to cars or widened to accommodate more cars, overall motor traffic volume increases.