Even by the lethal standards of Helmand province, where senseless death remains all too common, there was something particularly chilling about the killing of four soldiers on Friday when a 13-year-old boy pushed a wheelbarrow containing a bomb into the middle of a British army patrol.
Gordon Brown told troops in Afghanistan on Saturday that the use of a child suicide bomber was a "terrible commentary" on the Taliban. He went on to describe it as a "cowardly" attack and, by the afternoon, was saying it would "offend public opinion" worldwide. Clearly the British government believes such extreme tactics could not only divorce the Taliban from moderate Islamic opinion but perhaps even make its sympathisers in Afghanistan and beyond think twice.
Yet for an image so emotive, journalists need to ask: what exactly is the evidence? Could we be sure this child was a suicide bomber? Brown clearly has access to the most up-to-date information; he clearly believed what he was saying and was angered by it, which is why his words are all over Sunday's papers.
But shortly after he spoke, army sources in Afghanistan told me it was not yet clear the child knew what he was doing: he may have unwittingly been carrying a device that somebody else detonated. British troops are used to being approached by inquisitive children; this boy's demeanour did not seem unusual, apparently. Would it be more or less chilling if this boy was an unwitting rather than a knowing assassin? I'm not sure, but it would be different.
And how do we know he was 13? According to soldiers I spoke to, we don't: that was an educated guess. He might have been younger, he might have been older. Would it be any less shocking if he was actually 14, or 15? Not necessarily, but again, it would be different.
Brown's description may well prove accurate in every respect (although by the time of yesterday afternoon's press conference in Kabul, I noticed he was still condemning the Taliban in the strongest terms over the incident but being less specific about it being a suicide bombing). But it has been interesting to see the differences in the way the military and the political spheres approached the facts.
