There are currently eight Soryu-class submarines, and the recent announcement of an expansion of the Japanese submarine fleet from 16 to 22 likely means another 4-8 will be built. Both Australia and India have expressed interest in purchasing the Soryu class for their own submarine fleets.

Kyle Mizokami is a writer based in San Francisco who has appeared in The Diplomat, Foreign Policy, War is Boring and The Daily Beast. In 2009 he co-founded the defense and security blog Japan Security Watch. You can follow him on Twitter: @KyleMizokami.

Image: U.S. Navy Photo