It's true that the institutions of government in Britain have a good history of withstanding these kinds of attacks. But there are always consequences.
Apart from the poor people who were directly affected by the attacks, the long term sufferers will be anybody who "looks like a Muslim" (read that as "not white") living in London. During the IRA's campaign against the UK, anybody with an Irish accent was considered suspect by the cops, and this resulted in numerous mistrials and people being fitted up for crimes they didn't commit.
I predict a similar situation recurring, but this time it will be young asian men who are targeted. We have already had a taste of this with Hazel Blears, a government minister, and one of the East End chief constables (I can't remember which) saying that Muslims should get used to the idea that they will be stopped and searched in the street much more often than white people. This situation will get worse and breed more resentment.
I do hope none of the UK members here were affected by this tragedy.
Mick