Westminster attack: the questions security professionals will be asking

Londoners were well aware that the next terror attack in the UK was a matter of when, not if, as the acting deputy commissioner of the Metropolitan Police said soon after the incident at Westminster Palace on March 22.

To improve London’s response to terrorism, decision-makers will expect lessons to be learnt from this incident. Over the coming weeks, security analysts will dissect the attack. They will try to gain insight into the attacker’s plan, and reassess current security systems.

This was a test of London’s security arrangements. Even if it is considered to have been a test passed, questions will be asked.

Why was Westminster Bridge not better secured? Why was the perpetrator able to leave his vehicle? Why was he able to get through the Palace of Westminster’s gates and walk towards the sanctuary of democracy, even if it was just for a few metres?

Police secure Parliament Square. EPA

Security analysts will presumably dismiss some of these questions but come to note that, however horrific it was, this attack scenario was not an unexpected one.

Westminster is among the most protected sites in the UK and has been considered a key target for some time. March 22 must also have been considered a high risk date, given that it marked a year to the day since a series of coordinated terrorist attacks unfolded in Brussels.

Although rudimentary, the modes of attack and weapons used in the attack were expected, too. They are similar to those seen in the attacks in Nice and Berlin, and the Louvre knife attack in Paris.

The “crime script” of the attacker was equally unsophisticated: drive onto Westminster Bridge pavement, run over pedestrians and cyclists, crash car into railings, take two knives, walk to the palace’s Carriage Gates, walk towards the palace, stab police officer.

Reviewing security measures

Alongside the deaths and injuries caused by the attacker, this incident meant the prime minister had to be evacuated from the area, parliament was put on lockdown and parliamentary business was adjourned in both London and Edinburgh.

Some may feel that more should be done to reduce the consequences of attacks of this kind in the future. Others may argue that they cannot always be prevented and that the police’s intervention was both rapid and effective (and that the solutions to the weaknesses are to be sought elsewhere).

And indeed, given the nature of this attack, it’s difficult to see how to prevent a repeat event without changing the face of London.

Westminster Bridge has been considered a dangerous place since as early as the 19th century. Deaths and injuries caused by horse carriages were so frequent at the northern end of the bridge at that time that the authorities introduced the first (road) traffic light in the world there.

In the same way, this attack may stimulate the creation of innovative, affordable and non-intrusive physical protection systems. In the meantime, though, protective bollards remain a credible option to protect public spaces.

The wider installation of bollards (including automated retractable ones) was mentioned following the Nice attack on Bastille day. It was also mooted in a 2016 review of London’s preparedness to respond to a major terrorist incident and is considered a serious option against run-over attacks.

However, these proposals remain controversial. Many people oppose the securitisation of public spaces so the question of “how much is too much?” is always hanging in the air.

To answer it, policymakers will need to examine the deeply troubling question at the heart of terrorism risk management: if attacks by lone actors cannot be prevented, when is the damage so high that new measures should be introduced in our streets?