This article provides all the rationale that is needed for the Wikileaks leaks.  Peacenik is still hoping for something embarrassing for Harper to come out.  But Peacenik knows Harper has never been and will never be embarrassed about anything.  Least of all war crimes and war mongering.
It is for governments -- not journalists -- to guard public secrets, and  there is no national jeopardy in WikiLeaks' revelations.       
Is it justified? Should a newspaper disclose virtually all a nation's  secret diplomatic communication, illegally downloaded by one of its  citizens? The reporting in the Guardian of the first of a selection of  250,000 US state department cables marks a recasting of modern  diplomacy. Clearly, there is no longer such a thing as a safe electronic  archive, whatever computing's snake-oil salesmen claim. No organisation  can treat digitised communication as confidential. An electronic secret  is a contradiction in terms.
Anything said or done in the name of a  democracy is, prima facie, of public interest. When that democracy  purports to be "world policeman" – an assumption that runs ghostlike  through these cables – that interest is global. Nonetheless, the  Guardian had to consider two things in abetting disclosure, irrespective  of what is anyway published by WikiLeaks. It could not be party to  putting the lives of individuals or sources at risk, nor reveal material  that might compromise ongoing military operations or the location of  special forces.