After the Manchester attack, security could be a key election issue

Last night, at least 22 people were killed in an explosion at an Ariana Grande concert at the Manchester arena. Children are among the dead. A further 59 people were injured by the attack, which shook the venue shortly after the concert finished.

Islamic State has claimed responsibility, and a 23-year-old man was arrested this morning in south Manchester in connection with the blast.

This is the deadliest terror attack to hit the UK since the 2005 7/7 London bombings.

Witnesses have described the explosion as an “almighty bang.” Police believe the attacker was carrying an improvised suicide vest.

There was “a horrific stampede of people coming down steps, people falling on the floor,” one witness told the Financial Times.

This morning, Theresa May gave a statement outside No 10. She confirmed that the tragic event “is being treated by the police as an appalling terrorist attack,” and stated that police believe they have identified the bomber. She criticised the “appalling, sickening cowardice” of the bomber. Amber Rudd, the Home Secretary, has described the event as “barbaric.”

Beyond the immediate trauma of the attack, there will be concern about the long-term response to the terror threat by the government—and by society at large.

In the February 2016 issue of Prospect, Christopher de Bellaigue wrote that France was clamping down on extremism in the wrong way—and that its heavy-handed approach would prove counter-productive.

How May responds to the attack in the medium term may well prove to be significant. Political campaigning has officially been suspended—though the electoral clock has not stopped ticking, with postal voting already underway.

An attack at this late stage of an election campaign is not without precedent: the 2004 Madrid train bombings came just three days before the country’s general election, which many believe helped swing the country's subsequent election towards a shock defeat ofJosé María Aznar, who had been widely expected to win.

Closer to home, Jo Cox was tragically killed in the run-up to last year’s EU referendum – an event which some postulated might up drastically support for the Remain campaign, but which seemed, in the end, to have no large impact on the result.

Significantly, security has already become an increasingly hot political issue in recent weeks, with Jeremy Corbyn under heavy scrutiny for links with the IRA.

Whether Theresa May’s rather different reputation—as a former Home Secretary who prioritises security above all else—is bolstered in the aftermath of this attack remains to be seen. For now, the biggest concern remains the safety of British citizens—and the recovery of those injured in last night’s awful events.