So soon after Iraq, Britain is involved in another military venture of uncertain outcome. There are significant contrasts with the earlier misjudged calamity. Worryingly, there are some parallels too. In his Commons statement yesterday, David Cameron went out of his way to place a focus on international law and the limits of what is being planned. There was not a hint of crusading resolution in his restrained demeanour.
I am struck again by how the immediate past is the most powerful factor in determining a leader's approach. To some extent, Cameron has learnt from Blair and Iraq in the same way as Blair's calculations were made partly on the basis of his party's recent history. Blair was fearfully aware of Labour's vote-losing sequence in the 1980s when it was perceived as anti-American and "soft" on defence. In an attempt to redefine perceptions he got caught in a different nightmare, deeper than the one from which he had sought to escape. Conscious of Blair's nightmare, a subtext of Cameron's well structured statement might have been: "This is not Iraq."
The context is different too. Cameron was fortunate to have the support of France in his efforts to secure international support. France opposed Iraq. He is also incomparably better off with President Obama in the White House rather than President Bush. For all the premature criticism of the US president from parts of the gung-ho British media, Obama's caution and prevarication are preferable to Bush's restless indifference to the international community. Given the understandable wariness in the Middle East of Anglo-American military crusades, the scale of support is the necessary context for whatever follows and that support is wider now than it was a fortnight ago.
There are, though, worrying parallels with Iraq and indeed Afghanistan, as Britain goes into military action yet again. The first is trivial, but also eerie. After Cameron's statement in the Commons yesterday there was the familiar ritual of near universal praise, some of it verging on the ecstatic. MPs on both sides were eulogistic. Political pundits left the press gallery to tweet and blog glowing reviews.
Blair received the same adulatory coverage and bipartisan support when he delivered statements in the build-up to Iraq. Commentators hailed Blair's vision and courage. Tory leaders were so in awe they failed to discover the art of opposing him on any issue. When it all went wrong, the same commentators and some of the Tories turned on him.
It is in the DNA of the political classes to hail a prime minister embarking on military action and to change sides if the action goes wrong. If I were Cameron, I would take no comfort at this early stage from the eulogies. Announcing a military campaign is the easy bit, like announcing a comprehensive spending review, another guaranteed way of receiving high praise from the British media. The challenging part follows and opinion can turn.
Another echo is the degree to which foreign affairs will engulf the attention of another leader who had shown no great interest in advance. The practical consequences should not be underestimated if this is the start of a lengthy campaign. Geoff Mulgan, a senior adviser in No 10 during Blair's first term, told me regretfully several years ago that the Balkans conflict scuppered the domestic agenda soon after 1997 when a new government was at the height of its powers. Blair's time and attention became almost wholly diverted. There are differences now. Cameron has already unleashed a far more ambitious programme of domestic reform than Blair had done, so to some extent an unstoppable momentum is already established. But like Blair, Cameron skates thinly in terms of interest in policy detail. He will skate more thinly now because he will not have the time or energy to scrutinise the policy developments emerging from departments on a near-hourly basis as he addresses the consequences of military action.
The lack of clarity about what those consequences will be is the most alarming parallel with Iraq. At one point during yesterday's Commons exchanges, a Tory MP asked Cameron whether other leaders, most specifically Obama, agreed that regime change was the objective. With good cause Cameron made a distinction. While he and others wanted Gaddafi out, that was not the aim of the military exercise or the remit of the UN resolution. Cameron defined the objective as protecting people in Libya and "isolating" the regime, aspirations that are inevitably and perhaps dangerously imprecise.
The new UN resolution 1973 (a strangely diverting figure that conjures up surreal images of David Bowie as Aladdin Sane and the miners' strike from 1973) is not as ambiguous as the 1441 resolution in which Saddam was told to comply or "face the consequences". Famously none of the consequences were specified because there was no agreement as to what they would be. This one is clearer about the scope of action and the limits, but cannot address what happens if there is no smooth regime change in the near future.
So here we are again, undertaking military action without regime change as the declared objective, yet hoping that is the consequence, and without a clear plan as to what would happen if the regime falls or what form a democratic alternative would take. Nor is it clear what happens if the fighting is prolonged because Gaddafi stays put. What is the endgame, containment or regime change? If the leaders embarking on vaguely defined military action cannot answer clearly, they should not make the relatively easy early moves. I fear the overwhelming lesson of Iraq has not been learnt. Do not embark on a military venture without absolute clarity about the objectives and how they will be achieved.