In his Commons statement yesterday Mr Reid was careful to say that “we are not starting from year zero” and paid tribute to his predecessors for their “significant achievements”. But that is not the impression he has given as Home Secretary since taking over nearly three months ago, and especially since his “not fit for purpose” remarks.

His implicit theme has been that the Home Office needs a transformation, which was lacking in the past. Mr Reid has infuriated many of these predecessors, both official and ministerial, who feel that they have not been given credit for what they did.

The capabilities review, which gave the Home Office a lower rating than the three other departments surveyed, has been criticised for ignoring the political context and the achievement of priority targets on overall crime, drugs and criminals brought to court. In particular, some of the recent problems of the Immigration and Nationality Directorate (IND) are a direct result of Tony Blair’s decision to focus on reducing asylum numbers, at the cost of other immigration problems.

There has been a big expansion at the IND, from 4,000 to 20,000 staff, not all high quality. In the view of one insider, a 30 per cent performing institution has already been raised to 65 per cent. But that is a long way short of what is required, and expected, by politicians and the media.

What the IND needs now is a period of consolidation. But will the politicians allow this? Turning the IND into an arms length executive agency will work only if there is stability in immigration policy for the next five years. But when something goes wrong, who will appear on the Today programme: Liam Byrne, the Immigration Minister, or Lin Homer, the IND’s chief? Neat management lines can blur political accountability.

Moreover, many of the structural changes trumpeted by Mr Reid were started earlier under David Blunkett and Charles Clarke, and by Sir John Gieve, the former Permanent Secretary, and key officials such as Martin Narey, Leigh Lewis and Bill Jeffrey.

Examples are the reduction in the size of the headquarters staff, increased co-operation with the Department for Constitutional Affairs on criminal justice reform, the merger of the prisons and probation service and the recruitment of several outsiders in key positions. And after Sir David Normington arrived seven months ago, a further look at the Home Office was already under way before the sacking of Mr Clarke.

What Mr Reid has done is to pull some of these ideas together, add some of his own and give a fresh impetus to reform. Yet many of the key battles were fought before his time, just as Auchinleck’s great defensive success at the first battle of El Alamein halted the advance of Rommel’s Afrika Korps and paved the way for Montgomery’s much better known victory, and eventual breakthrough at the second battle of El Alamein that autumn.

Mr Reid is benefiting from the preparatory work of his predecessors. But he has to show now that he can achieve a breakthrough, justifying all the recent hype.

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