People anywhere in the world who claim not be profoundly disturbed by the self-publicized actions of the group of combatants that calls itself Islamic State (IS) provide considerable cause for concern.

It seems inhumane not to be horrified. But is it necessary, at the same time, to be petrified? I guess it depends on where you live. In areas contiguous to IS’ substantial domain, immunity to fear would be unnatural. On the other hand, does it make a lot of sense to be cowering thousands of miles away, in the United States, Britain or continental Europe?

Well, it probably does if you take at face value the purported likelihood of IS recruits or sympathizers indulging in terrorist acts over there. In countries such as the UK, Belgium and Australia, which appear to proportionately have provided more recruits for IS than comparable western nations, the received wisdom appears to be that some of the volunteers will be inclined to wreak havoc locally when they return.

By no stretch of the imagination can that possibility be ruled out. It’s likelihood, though, is tempered by a number of factors. Media reports suggest, for instance, that plenty of idiots who end up knocking on IS door are obliged to destroy their western passports as a gesture of commitment to the “caliphate.” That obviously makes it rather difficult to return.

Hundreds of volunteers, at the same time, are believed to indeed have returned to countries such as Britain and Belgium. None of them is claimed to have attempted any terrorist acts back in Europe, and in fact some organizations believe that most of those who return are disillusioned by what they witnessed and disinclined to disturb the peace.

Now that western airstrikes have been launched against IS in Iraq and Syria, there is yet another angle: Will those who were previously inclined to travel from the West to the “caliphate” zone now decide to stay home and do their worst over there? Again, the possibility obviously cannot be ruled out. Judging the probability, though, involves venturing into the realm of pure conjecture. But fear is an invaluable political device. A fairly egregious recent example was the final few weeks of the Scottish referendum campaign, when a broad range of politicians, bankers, captains of industry and the media strove in tandem to create the impression that a vote for independence would presage an unmitigated economic disaster.

The tactic appeared to work, arguably signifying yet another instance of the triumph of fear over hope. It’s by no means a one-way street, though. The eleventh-hour flurry of activity on the Scottish referendum front was itself driven by apprehension, once it belatedly became clear that a rejection of the independence option could no longer be taken for granted. A striking manifestation of this phenomenon was observed during the so-called Arab Spring, when unrest in Tunisia, which led rather rapidly to regime change, was being echoed within weeks in uprisings across the region. There’s inevitably a degree of irony in the fact that since then a new palette of fears has emerged.

The ongoing protests in Hong Kong, meanwhile, also reflect a casting off of fear — albeit by no means to the same extent as the gatherings that culminated so tragically in the Tiananmen Square massacre a quarter of a century ago. Back then, Beijing’s reaction succeeded in restoring order as well as fear; no comparable expression of popular dissent has occurred in the interim.

Tiananmen Square was sandwiched between a pair of intriguing occurrences. The 1988 protests in Burma prompted a ruthless reaction from that country’s military rulers and eventually led to the restoration of fear. In the case of the thankfully short-lived Soviet coup attempt of 1991, though, it was the would-be purveyors of fear who panicked as Muscovites, emboldened by the transformative political processes of the previous five years, emerged en masse on to the streets — and, crucially, military units refused to open fire.

It didn’t take all that long, however, for fear to be reintroduced as an instrument of rule in the post-Soviet era. Today, Vladimir Putin has no qualms about deploying it at will, while his adversaries in the neighborhood feel free to use it for their own ends. History shows that fear is a particularly potent part of the political arsenal when it comes to whipping up war hysteria. That’s unlikely to change. But its routine use for manipulative purposes in societies that lay claim to democracy and transparency is disturbing and deserves to be far more widely questioned than has thus far generally been the case. It would be salutary for Americans in particular to remind themselves of four-time President Franklin D. Roosevelt’s bold declaration in his first inaugural address to the effect that “the only thing we have to fear is fear itself…”