On November 5, more than 50,000 runners and two million spectators turned out for the New York Marathon. The event took place just a few days after a lone attacker drove a van into cyclists and pedestrians beside a busy Manhattan highway, killing eight people.
Security was beefed up for the marathon: sand-filled sanitation trucks were deployed at key intersections to block vehicles, while hundreds of extra police backed by sniffer dogs and snipers were positioned along the 21-kilometer route.
The precautions underline the changing nature of the terror threat, 16 years after the 9/11 al-Qaida attacks on the same city.
“They are moving towards the lower technology attacks, using knives, using vehicles, and using weapons that they can perhaps purchase on the black market but not have to make themselves,” said leading counter-terror analyst Brooke Rogers of Kings College, London.
He said, beyond short-term, enhanced security, an urban environment can adapt.
"For example, by having blast-proof glass installed in these grand glass structures. Or having different security measures, physical security measures – some of that could be scanning technology, some of it could be CCTV (closed circuit television) based, but also human measures, in terms of the staff not only walking around the perimeter, walking around inside with highly visible uniforms, but also staff who are less visible,” said Rogers.
In France, thousands of extra security personnel including soldiers have been deployed since the 2015 Paris attacks. But Rogers notes they have themselves become targets for terrorists.
London has installed physical barriers to separate vehicles and pedestrians in the wake of this year’s vehicle attacks in Westminster and on London Bridge. Permanent protection has been built around government buildings, with some of it adapted into street furniture like benches. But sectioning off every walkway is simply not practical.
“The amount of engineering that goes into those can cost millions of dollars. But we have to be careful because everything that we secure means that we are then turning the attention of these terrorist groups to softer targets,” said Rogers.
As a result, more attention is being given to educating the public. Since 2010 the U.S. Department for Homeland Security has been running an awareness campaign titled, "If you see something, say something". In London, the mantra is similar: "See It, Say It, Sorted."
British authorities have also issued a campaign on what to do if you’re caught in a terror attack – summarized as "Run, Hide, Tell."
Rogers says such campaigns aren’t pushed hard enough by authorities. “They’re very anxious that if they start making people think about that type of attack in the public places, that they’re going to frighten them and maybe scare them away. We have a lot of evidence that suggests that that is not the case. It doesn’t have a significant impact in terms of the perceived threat at all and in fact it builds higher levels of trust.”
Increasingly, security services see public awareness as a key line of defense against the changing terror threat.