[Lower Deck]

Because of debris. If it were a storm, then the sub would have dived below the surface.

There was no storm. The submarine submerged for a routine exercise and something went wrong. If it went below crush depth and imploded then some debris could make it to the surface. If it suffered an internal explosion, ala the Kursk, then debris could also have reached the surface.

How does sinking an Indonesian submarine help China rule the world?

[Robert DeLong]

Rome wasn't built in a day, and ambitious regimes take opportunities that are made available to them. Now it could very well be one of the things you suggest, but China is feeling their oats right now, especially if they could have done so without any one knowing the truth.

Note: I didn't say definitively that China sank it, just said I would bet that China sank it.

[Robert DeLong]

Looks like you may be right and I would have lost the bet

8>)