In the wake of the terror attacks in Brussels, we probably need to remind ourselves that while fighting this modern scourge is incredibly difficult, the tricky part is not to let official panic play into terrorist hands.
These attackers eagerly count on politicians and the news media overreacting, simply because that is so easy to do in a crisis-driven climate of fear.
We know the routine in which authorities, fearful of panic, scramble to "harden" their threatened societies by turning scores of possible soft targets into heavily armoured ones.
Swarms of police and soldiers, many now in ominous looking masks, race in to take up their stations around travel terminals, government buildings, public squares and the like.
Some of this so-called hardening of vulnerable targets is, of course, essential. No one questions that some reinforcements should be placed on real and symbolic targets. There is a role for defensive action when fighting terrorism.
But many counterterrorism experts now note there are drawbacks to the extreme barricading of Western cities, just as there are to excessively defensive mind-sets.
For starters each newly guarded target gives terrorists a cheap propaganda victory, even if they don't attack the site.
The projection of official fear is exactly what groups like ISIS want. It boosts recruiting, fundraising and rebel morale, and almost ensures crisis headlines whether their subsequent attacks are successful or not.
That is why one Australian study concluded that while some bolder security response is essential, "it is possible for the state to unintentionally inflate the value of some targets by proliferating security measures around them."
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Security police also point to an added tactical problem: New security screening procedures tend to cause vehicle or pedestrian congestion around entrances, which themselves become rich new targets. Soon these in turn have to be hardened.
The Israeli model?
So where does it end?
The overarching reality is that hardening police and military presence around high-profile sites soaks up finite security personnel while still leaving terror groups with an infinite number of soft targets to strike at.
Even if you do all you can to protect government buildings, airports or trains, terrorists can then go after shopping centres, schools, theatres and night clubs, which is what they did in Paris back in November.
What's more, expanding security budgets to push defences to the maximum, still leaves a problem, writes Harvard international affairs analyst Stephen Wall. For "who wants to live in the kind of police state that would be required to guard everyone all the time?"
The case is occasionally made in security circles that Israel's extremely hardened society can serve as an example for Western nations fixated on ISIS.
But Israel is a profoundly different social structure, one that has been long militarized and security conscious due to its external threats.
And even Israel has had difficulty deterring all attacks, such as the recent, sometimes fatal stabbings in urban centres.
Europe too fragmented
The blunt fact is that stepping up security in Western centres can achieve only so much, often not a lot, and future attacks in Europe and North America will surely occur.
Governments often balk at bracing their populations for this truth (while demagogues claim they can swiftly obliterate any threat through use of force abroad).
It's vital, though, not to fantasize about living in a totally risk-free future, no matter how much security we dare employ. The challenge is too complex for such innocence.
This doesn't mean we sink back into defeatism. There's much that a vigorous counterterrorism plan can achieve to confound terrorists and lessen their ability to spread fear.
In Europe, for example, Britain has led the way by pouring new resources into intelligence gathering, data-sharing among authorities and outreach to minority Muslim populations.
Last year, authorities said, seven separate terror plots were aborted by security forces there, serious setbacks for terror networks.
Across the European Union, however, the reality is discouraging.
Despite belated attempts by France and Belgium to better mesh their counterterrorism efforts, interagency rivalries, bureaucratic sluggishness and, above all, lack of data-sharing gives terror cells far too many openings.
So patchy is EU security co-operation that the former head of Britain's MI6 intelligence service, Richard Dearlove, dismisses most of its bodies as "little more than forums for the exchange of views" in which "the convoy must accommodate the slowest and leakiest of ships of state."
The thing to remember when you look at the carnage in Paris and Brussels is that there hasn't been a sustained coordinated offensive against terrorists in the EU.
Instead, what we have seen is a still disjointed effort by fragmented security services (not unlike the U.S. before 9/11, but much improved since).
Though a city of only 1.2 million, Brussels has 19 separate municipalities and six police departments.
What's more, there are only 1,500 members in the entire Belgian security services, while police strength in the notorious Molenbeck suburb, known as a breeding ground for plots, remains chronically short staffed.
As for police outreach into Muslim communities — what is called "de-radicalization" — Brussels police appeared to have dedicated only eight people to the cause.
Meanwhile critical social ills continue to fester in a nation often fractured between French and Flemish speaking populations, and which has failed to draw a disengaged Muslim minority of some 450,000 into its mainstream.
That is a constant reminder that social reforms are also urgently needed to deter militants' growth.
As for the broader challenge of global terrorism, nothing would offer more hope than ending the civil wars in Syria, Iraq and Libya, the greatest spawning grounds of transnational terror today.
That's a harder task than hardening the soft targets on the home front. But we'd better get it done.