IT'S understandable that people get frustrated with the media at times of national crisis like last week's terrorist attack on Westminster. Why the saturation coverage? Why do the terrorists’ job for them by giving the oxygen of publicity? Why not take tea and carry on?

Even I found it a little irritating hearing TV and radio presenters relentlessly probing policemen and politicians trying to find someone to blame. Was there an intelligence lapse? Why was this guy allowed to go about his murderous business when he was already on an MI5 watch-list? Why was the policeman who died not armed? Why were the gates open? It’s as if no-one could accept that sometimes there's nobody to blame except the terrorist himself.

The danger of this overwrought scrutiny is that it encourages politicians, under pressure to "do something"; to do something stupid. The security services have some 3000 “persons of interest” on their books, but the answer isn't to round them all up just in case another is about to go wild. Surveillance is intrusive enough, with CCTV cameras on every corner and policemen sifting through our internet history almost at will. Arming the police won’t help either – these people are happy to die.

Of course, political leaders sound weak when they fall back on predicable clichés and homilies: “Courage of the emergency services ... sympathy for the victims and their families ... we will not give in to terrorism ... democratic values must prevail.” Actually, I thought Theresa May’s speech in the House of Commons about “millions of acts of normality” defeating terrorism was really rather wise and hit exactly the right note. She did speak for the nation.

To be fair to the broadcasters, there is a reason why the media focuses so much on terrorist events: when they happen, other events largely cease. Governments halt initiatives and new legislation and the parties shelve policy announcements. Everyone remembers Jo Moore, the Labour special adviser who fired off an email to her colleagues on the morning after 9/11 advising that it was "a very good day" to "bury" bad news. The Scottish Parliament quite rightly cancelled its debate on Article 50 and relations with the single market. Having MSPs getting up and condemning Westminster rule would have sounded offensive.

The media is a massive machine for processing news and when there isn’t any news other than a terrorist incident it gets caught in a loop. In the news vacuum, speculation fills the gap. There is the inevitable soul-searching over immigration. Did the Westminster attack raise issues about multicultural Britain? Why are there communities which seem to reject British values of freedom, democracy and respect for human life? Sadiq Khan, the Mayor of London, raised eyebrows when he remarked that terrorist attacks were “part and parcel” of living in a global city. Some tried to construe this as callous defeatism.

Self-publicists like Nigel Farage surfed the media wave, claiming that mass immigration and multiculturalism were responsible for the outrage. He suggested a Trump-style Muslim travel ban might be a solution. But while the attacker Khalid Masood had a brown skin and the signature jihadist beard, he was born and brought up in Kent – where Nigel Farage himself was raised. By a bizarre coincidence, the former Ukip leader and the terrorist are the same age too: 52. A travel ban for middle-aged men from the home counties of England doesn’t really sound like it’s going to happen any time soon.

Nor was it legitimate to suggest that the Westminster bombing proved that free movement in Europe was a bad thing. Free movement had nothing to do with it. This terrorism was home-grown. The fragmentation of European anti-terrorism forces will only make it more difficult to deal with terrorist networks, as will the lapse into nativism and narrow nationalism. For this wasn’t so much an attack on British people as on citizens of the world. The victims of the Westminster car killer were from just about every country apart from the UK.

The Daily Mail columnist, Richard Littlejohn, blamed what he called the “yuman rites act”, as if human rights breed terrorism. “Politicians have turned Britain into a safe haven for terrorists from all over the world,” he fulminated, again ignoring the fact that Masood was as British as he is. Questions clearly have to be asked about how someone brought up in rural Kent of all places could turn into a mindless murderer. But the answer has nothing to do with the Human Rights Act.

There has arguably been a failure of integration, but it's not clear how closing down mosques and getting children to swear oaths of allegiance is going to prevent British citizens being radicalised. After all, Masood was in his sixth decade. Jihadism is a global problem which, like the weather, doesn't observe borders, laws or cultural norms.

Some newspapers tried to blame Google for allowing terrorist propaganda to be spread and for information on how to conduct bombings to be easily accessed by search engines There is an issue here, but no-one has a clue how to deal with it. The increased access to information that is the internet's undeniable contribution to civilisation also carries with it the risk that some of the information will be about things we would rather have hidden way. I am one of those who believe that the internet behemoths, like Facebook and Google, are publishers and should be responsible for what they publish, just as this newspaper is. But no-one wants outright censorship of the media.

Perhaps the only thing that can reasonably be said about the Westminster bombing is that it has brought home the nihilism of new-wave terrorism and served notice on how it is going to continue. This was low-tech as you can get. A solitary individual armed with a hired car and a couple of knives. There's no way you can stop someone like that getting through – not in an open society. It is as random and unavoidable as a road accident.

And at least he didn’t have a bomb. London has suffered far worse in the past. It is well worth looking up the timeline of bombing incidents in London during the IRA's mainland bombing campaign of the 1970s and 1980s. In these decades more than 100 died annually in the UK through terrorism. In the last 20 years the death toll has been one-tenth of that.

There was a certain grim irony in this terrorist attack happening as the former IRA commander turned politician, Martin McGuinness, was being buried in the Bogside, and being honoured by statesmen from across the world. The form of politically inspired terrorism he turned his back upon has been supplanted by the truly mindless terrorism of Islamic State. Unlike the IRA bombings that rained on London in the 1970s and 1980s, Salafism has no obvious political objective. For all their murderous irrationality and cruelty, the Irish Republicans had a clear set of political demands: a united Ireland and the removal of British troops. The means by which they sought to achieve this were hateful and wrong, but they could be reasoned with.

Khalid Masood simply wanted to kill non-believers. Islamic State tried to dignify this by calling him a “soldier” but he was not fighting for a cause. The objective was to strike fear and revulsion and encourage retaliatory action against Muslim communities which might turn them towards the ways of jihad.

But the big takeaway from last week is surely this: they didn't succeed. And so long as we keep calm and carry on avoiding simplistic solutions, they never will.