economics

The point is that cap­ital works – from a new police sta­tion to a new port – deliver a flow of ser­vices stretch­ing over 20, 30 or 40 years. Bor­row­ing to cover, say, half the cost of the work is a way of shar­ing its cost between the present and future gen­er­a­tions who will bene­fit from its ser­vices.
(full art­icle)

Ross Gittins is a genius – this art­icle is prob­ably the best explan­a­tion I’ve seen of why the gov­ern­ment should bor­row to pay for infrastructure.