What exactly do we need a public inquiry into the bombings for?
We know what happened. The bombings were perpetrated by four Islamic extremists who had been brainwashed by hate-filled bigots spouting a grotesquely distorted version of their religion. Their minds, no doubt, were all the more ready to accept what they were being poisoned with as a result of Britain's participation, against the will of a majority of the British public, in an illegal war and occupation in Iraq which resulted in the needless deaths of thousands of Muslims. Not that that excuses mindless violence perpetrated against innocent people.
There is no evidence of which I'm aware of serious failings on the part of the police, emergency services or intelligence. They can't be aware of the actions and intentions of every nutjob whose minds have been inflamed by the extremist bullshit that the bigots have been preaching.
Sadly, Britain (which, realistically, meant London) was going to be attacked by Islamic terrorists; it was a question of when rather than if. So I don't really see what there is to inquire into. Unless, of course, you're a conspiraloon who believes that there were no bombings, but the explosions were caused by the melting of the tube tunnels by gamma rays sent by lizards from the planet Zog who were in conspiracy with a dark cabal of Illuminati, Jews, members of Opus Dei and the Mafia to .... er .... take over the world, innit.
We know what "influenced" the attacks. It was Blair's evil and illegal war in Iraq. We don't need an expensive public inquiry to tell us.
I agree with you that such laws are oppressive and unnecessary, but what the fuck does this have to do with the question of whether there should be a public inquiry into the bombings?