This means 'war'

In his remarks to the Criminal Bar Association, the Director of Public Prosecutions Sir Ken Macdonald shackles together two separate things: (a) one is the call for a 'culture of legislative restraint' in dealing with terrorism, his concern for civil liberties and for maintaining the rule of law; (b) the other is his view that we should not think of the effort to combat terrorism as a 'war'. But the arguments for (a) do not depend on accepting (b), and in fact, assuming Sir Ken has been accurately reported, it is notable that he offers no persuasive arguments in support of (b). He is reported as having said:

London is not a battlefield. Those innocents who were murdered on July 7, 2005 were not victims of war. And the men who killed them were not, as in their vanity they claimed on their ludicrous videos, 'soldiers'. They were deluded, narcissistic inadequates. They were criminals. They were fantasists. We need to be very clear about this. On the streets of London, there is no such thing as a war on terror. The fight against terrorism on the streets of Britain is not a war. It is the prevention of crime, the enforcement of our laws and the winning of justice for those damaged by their infringement.
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Everyone here will come to their own conclusion about whether... the very life of the nation is presently endangered.

The type of terrorism that is at issue here is indeed not exactly like war in the paradigm meaning - as between states - but then neither is it just like ordinary crime. The combined facts of its overtly political agenda, its intentionally large-scale murderous character, its international scope - New York and Washington, Bali, Madrid, London, Istanbul etc - would seem to make the metaphor of a war perfectly appropriate. It is a war to be fought precisely in defence of the rule of law and the rights of citizens, against a global movement that doesn't care too much about those things.

What does Sir Ken Macdonald have to say against this way of thinking about the matter? (1) He has a few assertions, which are merely that - assertions. They presuppose rather than arguing for what he needs to persuade his audience of: thus, the murdered innocents, he says, are not victims of war, and there is no such thing as a war on terror. The short answers there are: yes, they are, and yes, there is. (2) He has the argument that terrorists aren't soldiers, because they are 'deluded, narcissistic inadequates... criminals... fantasists'. But that isn't a sound argument. They can be 'soldiers' of a sort - if the war metaphor is viable - as well as the other things he calls them (those of them that are indeed, for example, 'inadequates', as some of them may not be). That somebody is Y doesn't establish their non-Zness, unless being Y is incompatible with being Z. (3) Sir Ken suggests that this isn't a war because the life of the nation isn't endangered. But nor was it endangered during the Falklands War, which was a war, and nor has it been endangered during the Iraq war, which is a war.

The case against damaging Britain's traditions of freedom gains nothing from rejecting an entirely serviceable metaphor.