Reporting on nothing

When this read this article,

Japan detects foreign submarine passing near Amami-Oshima

my first thought was, "This is an empty report that potentially misleads."

Quoting the article (bold and underline my own):

it traveled westward through the contiguous zone around the island on Thursday afternoon.
The submarine did not violate Japanese territorial waters around the island, it said.

There was no international law that was broken. It is like a newspaper article reporting "An unknown person walked in front of the gate. He did not trespass the property."

What it does is to stoke suspicion about which nation the submarine belongs to. By deliberately not stating the nationality, it leaves it up to the reader to imagine, which usually becomes a self-reinforcing loop. We will use this to confirm our suspicion. Even though there was no fact provided.

For all we know, it could have been a U.S. submarine. Given that it is outside territorial waters, any nation's submarine could have operated there legally.

Sometimes, you do not need to provide false information to mislead. Not providing key information can have the same effect.