According to Seita Kanai, head of research and development at Mazda, the Japanese automaker would need to sell at least 10,000 diesel engines in the States to make a profitable business case. Not surprisingly, Mazda is studying Volkswagen's recent success in offering diesels here in America to see if there's any chance of moving the required units.
Whatever the case, we know that Mazda has some worthwhile new powerplants that we'd love to see installed in the engine bays of products like the current Mazda3 and upcoming Mazda2.
[Source: Automotive News - Sub. Req'd]