Another one who agrees - battle talk is inappropriate, at best. If it helps some individuals to think in battle terms, thats absolutely fine, but a national campaign is not directed at just those individual personalities.
FWIW, when I had a life-threatening illness to tackle I did so with massive amounts of fear, occasional despair, gave in to depression a few times, as well as just getting on with it. Feeling it all was my way of dealing with reality and staying sane, and it didn't stop me getting well.
I also think this attitude of 'be brave, fight, don't let the bastard get you down' is pretty pervasive in our culture generally...left over of the 'stiff upper lip' times maybe....infertility? 'Just relax!' Miscarriage? 'Avoid stress.' Depression? 'Pull yourself together' 
There are times when our attitudes make a difference, even huge differences in our life experiences - but they do not cause cancer (or infertility, or miscarriage, or flu, etc etc etc)
As for the campaign, there are so many better lines they could use.