The US Navy should procure a fleet of diesel-powered subs. Not only are diesels cheaper than nuclear-powered subs, but they have the advantage of being better platforms for many of the tasks the Navy faces today. The list of actual and potential submarine missions, including close-in intelligence, surveillance and reconnaissance, special operations, and blockade and mining, continues to grow.
These growing operational demands are coupled with the exigencies of new undersea requirements. In addition to the deep-sea dives and prolonged blue-water missions that became the staple of submarine operations during the Cold War, there are a number of scenarios today that are focused on the littoral areas, the green water within 100 miles of land, be they in the strait of Hormuz or Malacca, off the shores of Taiwan or in the South China Sea.
It is these missions that often favor diesel submarines. Diesel subs are smaller, stealthier and more maneuverable in tight spaces than nuclear submarines. For example, unlike a nuclear submarine's power plant, a diesel's primary engine can be turned off when submerged, reducing noise emission. Indeed, unlike a nuclear-powered submarine, a modern diesel can hide on the ocean's floor, deadly silent, while monitoring whatever passes over and around it.