There's a lot of anguished head-scratching these days in the higher echelons of foreign policy wonkery. The question being asked is this: has the Iraq disaster (and an impending Afghanistan disaster?) put paid to any idea that rich, stable democracies can encourage more such paragons of political virtue in parts of the world where they are currently conspicuous by their absence?
Yes, said the foreign secretary David Miliband in a in Oxford on Tuesday: "We cannot impose democratic norms. But we can be clear about the desirability of government by the people and clear that without hubris or sanctimony we can play a role in backing demands for democratic governance and all that goes with it."
It's been a supremely appropriate week for him to tackle this - with two of the earliest examples of pro-democracy interventionism back in the headlines, but for all the wrong reasons. He mentioned neither of them, so I will: Kosovo, and East Timor.
Let's take East Timor first. In 2002, it became an independent, sovereign nation after a lengthy UN-sponsored transition from nearly 25 years of Indonesian occupation. It was heralded as a wonderful example of how concerted foreign intervention can end oppression and facilitate self-determination. This week, renegade soldiers shot and seriously injured the president, Nobel Peace Prize winner Jose Ramos Horta, and ambushed the prime minister, Xanana Gusmao. Neither the Australian-led UN peacekeeping force, nor the UN police, were able to prevent the attacks.
The Kosovo story dates from the same period: the NATO intervention in Kosovo was in March-June 1999; the UN-sponsored independence referendum in East Timor was in August of the same year. And in April 1999, Tony Blair made his famous speech: "The most pressing foreign policy problem we face is to identify the circumstances in which we should get actively involved in other people's conflicts."
This weekend, Kosovo is expected to declare its independence from Serbia. It will be recognised by the US and much of the European Union, but not, all importantly, by Serbia itself, which regards it as a secessionist province, or by Russia, which will veto any attempt to obtain UN membership for Kosovo. A period of renewed Balkan instability is forecast.
So neither Kosovo, nor East Timor, on the face of it, are good examples of the benefits of foreign intervention - although it may well be argued that in both cases, things might be a good deal worse had outsiders not intervened. Both, in their own ways, can be described as democracies: East Timor is independent because an overwhelming majority of its people voted for independence in a referendum; Kosovo will declare its independence because that is what the overwhelming majority of its people want.
But what we are learning is that the spread of democracy does not in itself necessarily bring with it greater stability. And perhaps we are learning too that democracy which comes as a result of homegrown grass-roots pressure is more likely to prove enduring than when it comes from outside. Mr Miliband, in his speech, cited the examples of Taiwan, the Philippines, Indonesia, many countries in Africa, and all of Latin America except for Cuba, as countries where democracy has been successfully introduced or re-introduced over the past three decades. In few, if any of them, it could be argued, has foreign intervention played a major role.
In the case of post-Soviet central and eastern Europe, it was more likely to have been the discreet but well-targeted financial assistance from organisations like the , which encouraged the formation of political parties, radio stations and independent newspapers and thus helped create the conditions in which a genuine, if imperfect, democracy could begin to grow. It's a lesson not lost on President Putin of Russia, who has cracked down hard on organisations that he suspects may have been trying to do something similar under his own nose.
In the late 1990s, the over-riding foreign policy imperative was: No more Rwandas. Western governments were appalled at the 1994 genocide that had been unleashed in that country - never again, they said, will we stand by while thousands of people are slaughtered.
But after the attacks of September 11, 2001, the imperative shifted. It became: No more Afghanistans, no more failed states in which terrorist groups can organise attacks on the West. But what do we see in Afghanistan today? A weak central government, a resurgent Taliban, and a bigger opium harvest than ever.
So far, say some analysts, it is hard to point to examples of where foreign intervention has successfully led to a stable and lasting democracy. (Japan and Germany in the immediate aftermath of the Second World War are the most often quoted examples, but arguably they were special cases in unique circumstances which have not applied anywhere else since.)
From Cambodia to Afghanistan, from Kosovo to East Timor, it's a lot easier to go in, full of good intentions, than to leave with mission accomplished. The debate continues ...