Copenhagen is getting all the headlines, but it’s not the only news out of Europe this week. Equally enthralling is the continuing British inquiry into that country’s involvement in the Iraq war. Public hearings began two weeks ago, and although so far they have barely scratched the surface of the inquiry’s task, there has already been some fascinating testimony.

Yesterday the inquiry heard from Major-General Tim Cross, who was Britain’s representative on the Iraq reconstruction authority. He described telling Tony Blair two days before the invasion that it should be delayed due to lack of preparation: he “did not believe postwar planning was anywhere near ready”.

It’s hard so say which is sillier: a government that ignores its own advisers’ view that it is going to war unprepared, or a senior military officer thinking that there is some chance of postponing an invasion that is set for only two days off.

But the Iraq war inquiry is greater than the sum of its parts. From vignettes such as  that of Major-General Cross, a larger picture is being built up of how Britain went to war. It is not pretty. (The BBC has excellent summaries of the background to the inquiry and the evidence presented so far.)

When the inquiry was announced, there was understandable scepticism about whether the government would really allow a wide-ranging investigation of its decision to go to war. The inquiry was criticised for its lack of technical and legal expertise, and for the fact that it will not report until after next year’s election. Indeed, the unwillingness to probe too deeply probably extends to the opposition as well, since they also supported the war — David Cameron defended it, with evident reluctance, in a Guardian column.

But from the government’s point of view, there were no good options. Facing electoral oblivion, Gordon Brown had to try something, and even if it gave no benefit to the government, the thought of taking Tony Blair down with him must have had some appeal. He might also hope some of the mud will rub off on his main leadership rival, Blairite David Miliband.

So the inquiry looks like being more revealing than such exercises usually are. Although lawyers have criticised the lack of a lawyer on the panel, the legality of the war is not really the key issue. Everyone knows the war was illegal; no serious international lawyer not in the pay of one of the belligerents has ever said otherwise.

The key questions are factual: when did the Blair government commit itself to the war? What advice did it rely on? How explicitly was it warned of the consequences, for Iraq or for Britain? Was there ever a point when a different decision in London could have halted the American drive to war?

Regardless of what the inquiry’s report eventually says, the testimony it receives on these questions will provide plenty of food for thought.