Do we still need political parties?

In many Western countries, party structures are dissolving. Traditional political organisations are disintegrating, being swept away by new movements, or infiltrated by fresh members.

There is not much left of the once-defining role of classical parties. And the examples are abundant.

In France, the traditional party system has decayed. The Socialists, after being the governing party in Paris until spring, have practically ceased to exist.

Other traditional parties have a...