If no one else will say it:

This is media spin for constructing popular opinion.  Rightly, I'd add, though I agree that it's not technically correct.

Taking a weapon and killing people is in one way *not* a cowardly act: the murderer (in these cases) will clearly be apprehended and their life will be over (through prison or death sentence).  The public interest is served by **not** framing this as any-form-of brave.  That would provide praise to the murderer(s).


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The only way that "cowardly" can rightly apply is if we consider the murderers had *other ways* to forward their cause (e.g. politics).  Instead of conducting a peaceful revolution, they 'take the easy path', which is 'cowardly'.



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I have a personal hunch that the usage around around 2001, when media needed a way to condemn suicide bombers for attacks on the WTC.  Many suicide 'missions' are performed out of a concept of 'honor'.  Publicly-labeling these people as cowards is (perhaps?) the strongest response to in swaying the opinions of those that would 'try next.'  This being a more effective response than to use any term that would convey power - even that the murderer(s) had the power to be brutal and savage.