The head of MI5 has lost the plot. Britain is safer than ever in its history | Simon Jenkins

Oh my God, the Muslims are going to get us. Watch out. Our national security is “more under threat than ever”. Our lives are seeing a “dramatic upshift” in threat levels, with “plots from overseas, plots online, complex scheming and crude stabbings, lengthy planning but also spontaneous attacks”. MI5 boss Andrew Parker seemed close to a panic attack on Tuesday. He found threats “at the highest tempo I have seen in my 34-year career”. We should clearly be shaking in our shoes, and give Parker every penny he demands.

From a head of state security, this is rubbish. During the years of IRA terrorism, annual killings ran at 10 to a hundred times the present rate. But ever since they “came out” in the 1990s, spy chiefs have built bureaucratic empires on the blackmail of fear. It is a revival of Eisenhower’s notorious “military-industrial complex”.

Parker’s primary obligation is to keep Britain’s borders, its institutions and its economy safe from enemy attack. By no stretch of a spy’s fervid imagination can random terrorist incidents constitute an assault from a plausible enemy. Britain today must be safer from siege, conquest or revolution than at any time in history.

A secondary obligation on Parker is to be a source of reassurance, not a purveyor of fear, least of all when there is nothing the public can do in response. Fear is the most toxic of all authoritarian weapons. It should not emanate from the mouth of a British public servant. Parker’s obligation is to secrecy, discretion and proportion. He shows none of them.

After the collapse of Soviet communism, the security services were bereft of a commensurate enemy. At first, they chased drug lords and money launderers, to no effect. Then they found a saviour in Tony Blair’s “weapons of mass destruction”. Saddam’s rusting silos, Gaddafi’s yellowcake uranium and the ayatollahs’ centrifuges were a godsend. Any dodgy dossier would do. A half-baked Birmingham bomb factory or a demented tube stabbing was good for “an attack on the nation and its values”. Police budgets were cut; spies boomed.

Fear and hysteria soon gained traction as politicians were terrorised by counter-terrorism. They forgot that terror is not an ideology but a methodology – a means to an end, not an end in itself. Every text on terrorism stresses that it cannot be “defeated”, as Blair promised, any more than a knife or a bomb is defeated. Terrorism is the use of criminality for an ulterior motive.

Islamist supremacy may be a perverted motive for mayhem. But to suggest that such mayhem undermines the security of prosperous and well-defended states demeans the robustness of such states. It is an abuse of language. Worse, it is exactly the abuse terrorists want to hear. How stupid can we get?

The wars Britain has been fighting in various parts of the Middle East since 2001 have neither improved – nor worsened – Britain’s security one iota. They have merely spent billions of pounds attacking poor countries and killing thousands of people who never posed any threat to Britain. They have been inexcusable. My bookshelf groans with their cruelty and counter-productivity, a catalogue of fallacious excuses, bombings, killings and drone attacks, all occasioned by a single act of terror, by Osama bin Laden on 9/11.

What these wars have done is incite a spate of killings on British streets, the precise opposite of their justification by Blair, Gordon Brown and David Cameron. Some of these killings have been conspiratorial, some “lone wolf”. Many have been thwarted by the police and security services, which is their job. All have been tragedies to those killed and injured. But personal tragedy is not the same as a “threat to national security”.

If you want terror in modern Britain, note what was happening as Parker was making his pitch. Two more moped stabbings in west London took the epidemic of killings in the capital to 133 in the past 12 months, compared with 106 the year before. Figures do not record how many were of or by Muslims. Because few were accompanied by cries of “Allahu Akbar”, they went down as common murders, rather than an assault on the integrity of the British state.

Parker boasts that he has foiled “20 terror plots in four years”, which is what his office is paid to do. But what of gang violence up 18% and youth killings up 84% in the capital while resources have been bled from the police into his? “Terror” crime is up too. But clothing it in the language of statism, war and patriotism does not alter the fact that his terrorists, like London’s gangsters, are really just another grim statistic from Britain’s hidden margins of urban life – and best treated that way.

The use of explosive violence for quasi-political ends is as old as dynamite. The violence achieves its end, if at all, not by its horror but by how society reacts to it. British governments were right in the 1970s and 1980s to treat IRA terrorist acts as criminal not political, even though they were aimed specifically at breaking up the United Kingdom and thus political and “existential”. Murders were regarded as murders, and other channels were used to confront the IRA’s motives.

This is why the government’s misnamed and ham-fisted “Prevent strategy”, to sow British values in Muslim neighbourhoods, does at least make sense. There is simply no alternative. It is also why there is no glamorous “military” substitute for the hard grind of local intelligence through local policing, in the communities where killers may lurk. If MI5 has any role in this, it is surely its best-kept secret, not trumpeted from the rooftops.

Hence the warning of that sober student of terror, Richard English of Queen’s University Belfast, that the “most serious danger currently posed by terrorists is their capacity to provoke ill-judged, extravagant and counter-productive state responses”. It is not acts of terror that we should fear, but our inability to modulate our reactions to them. These reactions include the words we use to describe these acts and the liberties we curb to constrain them.

Terrorist killings are appalling, but they are not threats to national security. As long as the head of MI5 cannot tell the difference, I fear for national security.

• Simon Jenkins is a Guardian columnist