Rethink should sink navy's new ships

Sometime very soon, the Defence Department will ask the Prime Minister and his colleagues to decide who is going to design and build three new destroyers for the navy. This is a serious business, because we are talking real money here - upwards of $6 billion. But before ministers get down to the detail of comparing bids, they should ask the department an even more serious question: why exactly are we buying these new destroyers in the first place? Big grey ships are such an icon of national power that the logic of building them seems self-evident. But a country of Australia's size in a region like ours cannot afford to be sentimental or simplistic. Ministers need to be sure that this is the most cost-effective way to spend the billions needed to build the ships, and the billions more to maintain and operate them for decades.