I find this to be an excellent, excellent photograph, "made" by the emotion of the man holding the poster.
I'm never sure how "deliberate" these things are (in my personal experience, the often are not, but in retrospect they could just as well have been) but I love your framing - the focus is not on the man at all, but on the war protest.
Yet, his inclusion adds that crucial touch of personal emotion that makes a great photojournalistic image. By looking into his eyes, one cannot help but imagine his reason for being there - I imagine it could be deeply personal (i.e. maybe he has a son in the armed forces) or that he simply deeply cares about the greater good here.
Well done!