After the world was saved and temporary peace occurred, what is implied when Rorschach's journal (he left it before he's going to deal with Adrian Veidt) is found?
As Dr Manhatten says "Nothing ever ends"
At the end of Watchmen, Rorschach is dead, and the others have agreed to keep silent on Veidt's plan for peace, that millions have died for.
The journal has all Rorschach's notes, says whatever happens Veidt is responsible and ends with Nite Owl and Rorschach heading for Antarctica.
The danger is the New Frontiersman editor (who is fed up of the peace with Russia already) will read it (as Seymour is about to bring it over), put two and two together, and expose the secret, probably heading the world back to Armageddon.
It also raises the point of Rorschach's claim to never compromise "even in the face of Armageddon" as although he looks like he's given in to peer pressure on Veidt by allowing Dr Manhattan to kill him, he has actually sacrificed himself to ensure the journal isn't stopped.
To me Rorschach's journal getting into the hands of the New Frontiersman is to raise a question:
Is it worth?
Do 3 million people's lives mean nothing for achieving peace? Is the truth needed to be hidden? Was Rorschach's attempt before his death wrong?
In Rorschach's words:
Rorschach: Never compromise. Not even in the face of Armageddon.
So even after his death, his work was not done. Truth must be spoken.