If it seems like every week, there’s another terrorist attack – well, you’re not wrong. According to one crowdsourcing map, there have been over 500 attacks around the world since the start of 2017, with over 3,500 fatalities. For a period in 2016, ISIS-initiated attacks were occurring, on average, every 84 hours.

Many Americans might be wondering, in the wake of so many attacks, how vulnerable they are and what security measures are now in place. There’s also the question of what law enforcement can do better.

In 1992, I founded the Georgia International Law Enforcement Exchange (GILEE), which helped train law enforcement leaders from more than 20 countries and more than 20 states. GILEE would go on to provide significant security assistance to the Olympic Games in Atlanta, Salt Lake City, London and Rio.

Despite improvements in methods and coordination among law enforcement agencies over the past 25 years, they’re still hamstrung in a number of ways. With large public gatherings of people becoming more attractive targets for terrorists, what are the best strategies moving forward?

The limits of physical security

Even though Atlanta had six years to implement a security plan for the 1996 Olympic Games, it didn’t emerge unscathed. On July 27, 1996, Eric Rudolph detonated a homemade pipe bomb shortly after making a warning phone call. Though the bomb left two dead and more than a hundred injured, it could have been far worse (the backpack containing the bomb had been repositioned on the ground, which mitigated the blast). While the IOC decided to continue the Olympic Games, the attack left a black mark on an otherwise successful event.

The bombing in Atlanta happened at the only public venue that remained unsecured because it was free to the wider public. Had security been applied at the Olympic Park, Rudolph wouldn’t have been able to enter with the bomb in his knapsack.

Recognizing the threat posed outside of venues, Olympic security costs have since grown exponentially, and include more personnel and more sophisticated technologies. While Atlanta is estimated to have spent US$200 million, London spent over $1.5 billion. Tokyo in 2020 is projected to spend about $3 billion.

Meanwhile, following 9/11, airports around the world have implemented new security measures, such as TSA’s enhanced screening technology, baggage handling, pat-down screening and secure airport design. It’s become standard procedure for large sporting and entertainment venues to have security checks at the gates.

But despite huge budgets and the presence of thousands of added security personnel, it’s virtually impossible to prevent a determined terrorist, or guarantee absolute safety. While security efforts for events like the Olympic Games have escalated, terrorists today no longer wait for major events that draw global interest.

Instead – aware that their attacks will generate massive amounts of media attention on their own – they’ve gone on to hit theaters, airport terminals, sporting events, hotels, buses and areas outside arenas.

All have two things in common: crowds of people and an attack carried out with relative ease.

Heightened security has issues of its own. It can create backlogs of people, and during the Atlanta Olympics, venue commanders lowered the sensor levels to speed up lines that were too long. While potential terrorists may not have known this, it still risked letting someone in with a bomb.

And if many people need to wait in line to go through security, a would-be terrorist can detonate a bomb outside the venue. This is exactly what happened in Brussels and Istanbul.

Conceptualizing the threat

The war against terrorism is a form of asymmetric warfare.

It’s a far cry from traditional wars, in which uniform-wearing armies face off on the battlefield. Instead, it pits defenseless civilians against determined terrorists wishing to cause them significant harm.

The odds are in favor of terrorists. All they have to do is succeed once, no matter how many times they try. For public safety professionals to be fully successful, they have to prevent 100 percent of the terror attempts. It’s a number to aspire to, but even the most experienced countries fighting terror – such as Israel and the U.K. – can’t measure up to this standard.

These days, it’s necessary to consider any place where crowds congregate as vulnerable “soft targets” for the attackers.

To better prepare for securing soft targets (and this isn’t to say threats against “hard targets,” like planes, buildings and infrastructure, have diminished) law enforcement agencies must improve coordination among one another, whether it’s via intelligence, information sharing and training. And then there’s the need for deconfliction, which refers to avoiding self-defeating behavior – from interagency rivalries and poor communication to insufficient coordination – by people who are on the same side.

For example, the five-county Atlanta metro area has 60 law enforcement agencies – and that doesn’t even include state agencies, federal agencies, fire response and emergency medical services. Despite these myriad organizations, Atlanta is probably one of two of the best-prepared cities in America to deal with terrorist threats (the other is New York City). I’ve witnessed, in my role as a law enforcement trainer, how the experience of past attacks has engendered an organizational culture of cooperation in these two cities that’s unprecedented in law enforcement. Many heads of federal law enforcement agencies aspire to have a stint in Atlanta because they learned about its reputation for coordination and cooperation in areas such as intelligence, planning, communication and deployment.

Better cooperation among agencies is possible, though not easy, to implement. Yet even this isn’t enough.

Given that there is no way to guarantee complete safety, and that the threat assessment expects more attacks, there are two more elements that ought to receive more attention: community resilience and community policing.

Resilience refers to how a community mitigates the threat of terrorism and how it recovers from an attack. The idea is not to let the terrorists have a sense that they are able to disrupt life. So a great effort is dedicated to return to “normal life” as rapidly as possible, to rebuild and reopen what was destroyed.

Community policing means using the community as a resource to minimize the spread of radical ideologies. By informing and supporting law enforcement through proactive partnerships, citizens can become key players and reliable partners in what some call “co-produced” public safety.

These strategies won’t provide absolute security. But they will help minimize attacks and get us closer to that golden 100 percent standard.

Robert R. Friedmann does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.