A year and a half ago I marched in London against the approaching war in Iraq. The march attracted the usual ragtag coalition of anti-establishment groups - Quakers against the bomb, supporters of Palestinian liberation etc; and also a young woman selling newspapers in support of the Colombian FARC rebels. My then fiancée (now my wife) is Colombian, and I have spent a lot of time in Medellín, in the heart of one of the areas worst affected by civil violence in Colombia. My wife knows of more than one person in her circle of friends who have suffered kidnap in the family. (The rebels' income is based partly on kidnap and extortion, often involving a periodic adjustment upwards of ransom demands and indefinite delays in returning hostages.)

The current government in Colombia has the confidence of many in the country who were fed up with attempts to negotiate with the rebels - widely regarded as a spent force in terms of any ideological coherence, and now simply a self-perpetuating institution dedicated to organised violence. I'm told kidnappings are down for the first full year of the president's term, and that's good enough for many.

I imagine if I were more ignorant of conditions inside Colombia I would likely follow anti-establishment herd instinct and assume that there can be no good in a right-wing ally of George W Bush (am I not either with him or against him?), that the FARC are no doubt a misrepresented liberation force etc. And in fact I realise that it is almost impossible for me to know the truth, if truth exists, of the messy situation, because journalists who pursue a "left-wing" line in criticism of government policy or in support of the rebels are in constant danger of violence from the "right-wing" paramilitaries.

But I do feel genuinely challenged by this situation, and I'm posting to ask for the views of people with knowledge of what's happening in Colombia. My basic question is: what is a democratically elected government supposed to do when faced with organisations and individuals who are determined to attack its citizens? On the one hand it seems obvious that it must defend its citizens by force, and that a failure to do so effectively over the years has led to a shrinking of the space for peaceful civil society, to be filled by opposing forces dedicated to extreme violence. Surely laying claim to a political label should not provide impunity for the exercise of that violence. On the other hand, it's good to negotiate, and civil conflicts have rarely been effectively resolved through force alone (Northern Ireland would be the textbook example here) - and I suspect that the information that reaches me about the conflict is heavily filtered and propagandised.

It's hard to discuss these subjects without arousing great anger - and I feel strongly myself. But I would genuinely like to hear some thoughtful views if possible, to help me find a way through this morass.