Back in April 1986 I was the FCO Resident Clerk on duty on the night US warplanes attacked a number of targets in Libya.

The then British Government led by Margaret Thatcher of course knew this was coming, having given permission for some of the US aircraft to deploy from bases in the UK. The FCO had set up an emergency unit to try to manage the expected storm of political and other protests round the world; I as Resident Clerk was expected to deal with the public.

I remember stopping by the Emergency Unit to see what was happening, to be told in a tense voice that the aircraft would be rounding Gibraltar en route to Libya in the coming minutes. None of us knew what would happen. Would widespread war break out? Would our friends and colleagues in Embassies round the Arab world be attacked in revenge?

As news of the attacks broke, the FCO switchboard was soon swamped with callers calling to express in vigorous terms their indignation and anger at this turn of events. I spent hours politely thanking them each for their calls and urging them to contact their MPs or otherwise make their concerns known to the Government in a rather more systematic way.

Maybe I had lacked imagination previously, but this episode brought home to me for the first time that in my own rather limited and indirect way I was a non-trivial part of (and as it turned out some sort of spokesman for) an elaborate process which had led to some people far away dying violently. That a diplomatic service career sometimes involved grim moral dilemmas. And that if that was not what I was ready to face in a job, I should get another one.

How do we measure that Reagan power-play after two decades? Colonel Gaddafi is still there. Did the bombing (in part aimed at him personally) eventually give him cause to reflect on the wisdom of promoting terrorism, enabling his much later reconciliation with British and European leaders? Did it also help ratchet up the virulent Islamist fundamentalism we now see? Both?

When NATO forces bombed Serbia in 1999 in response to Milosevic’s brutality in and around Kosovo the idea of going after Milosevic personally seems to have been rejected. Hundreds of ordinary Serbs were killed and maimed, soldiers and civilians alike. Milosevic and his appalling family scarcely suffered, at that point at least.

Likewise sustained sanctions helped destroy much of Serbian society, indirectly killing more people and doing damage whose costs compound up down the decades. A Milosevicised gangster elite emerged and prospered; their predominance helped bring about the assassination in 2003 of the most European-minded of all recent Balkan leaders, Serbian Prime Minister Zoran Djindjic.

Hmm. Diplomacy reaches Limits. Above all the limit of dealing with Bad Leaders who build up enough domestic power to be able with impunity to wreck their own countries and export disorder elsewhere, and who are just not open to any sort of normal fair-minded arguments.

Going after Bad Leaders in the Reagan way may not be popular. But are the alternatives really so much better in the longer run?