A DAY or so after last week’s Boston marathon bombings, a local luminary solemnly declared that there could be no possible justification or explanation for the outrage.

The first part of that statement is incontrovertible — and it is in fact somewhat surprising that so many foreign leaders, in expressing their condolences, thought it necessary to signpost the unjustifiable nature of that act of violence.

Perhaps, in such circumstances, stating the obvious serves as a cover for not having much to say beyond pledging allegiance to the United States of America as it experiences a painful pinprick relative to the nations where terrorism consumes lives on a more or less daily basis.

It’s still a bit odd, though — implicitly suggesting that there could be a coherent alternative narrative. There can’t, at least not by any rational measure.

There has got, on the other hand, to be an explanation, and to not seek it would be tantamount to criminal negligence. Fortunately, most Americans are keen to know why the brothers Tsarnaev behaved the way they did. Unfortunately, a complete answer may never be forthcoming.

The Chechen connection is a bit of a curve ball — not just for the average American, who is unlikely ever to have heard of Chechnya, but also for most terrorism experts, who are finding it hard to draw a connection between the historic restiveness in that Russian territory and the desire to wreak havoc on American soil.

Chechen anguish in the modern era stretches back to Josef Stalin’s deportation of that ethnic group from its homeland towards the end of the Second World War. An estimated 30 per cent of Chechens are believed to have perished as a consequence. They were permitted to return under Nikita Khrushchev, but the desire for independence lingered on, evidently, for the next four decades or so, when the break-up of the Soviet Union offered another opportunity.

Two wars followed, wiping out another 20pc of Chechnya’s population. An abortive bid for independence under the secular leadership of Gen Dzhokhar Dudayev — assassinated in 1996 — eventually made way for an Islamist insurgency. That, too, was crushed, but not exactly eliminated. It seeped through into neighbouring regions, notably Dagestan.

Hitherto, however, Chechnya-related terrorism has tended to target Russians — invariably innocents in Moscow. Salafism in Chechnya and its surrounds was bolstered by recruits from abroad, but a Chechnyan role in foreign violence was not really on anyone’s radar until last week — although Ramzan Kadyrov, the region’s pro-Putin leader has been suspected of sending his thugs to murder exiled foes.

Last year, Tamerlan Tsarnaev, one of the suspected Boston perpetrators, spent seven months with his family in Dagestan. Acquaintances and family members have been quoted as saying that he had veered towards fundamentalist Islam well before then.

It appears that Russia requested the FBI to investigate him in 2011. The FBI did, and found no obvious cause for alarm — although the fact that he was interviewed may have been crucial in persuading the US authorities to delay processing his application for citizenship.

The FBI has lately been criticised for its failure to recognise him as a threat, but it is perfectly conceivable that two years ago Tamerlan had no violent intent beyond the time he spent in the boxing ring. It would certainly be interesting to know, however, what exactly alerted the Russian authorities to him. It may have been nothing more than his internet profile, which reveals an interest, via YouTube, in jihadist diatribes.

Then again, no evidence has emerged that he was under surveillance during his sojourn in Dagestan. It is also far from clear why his father sought, and was granted, political asylum in the US in 2002, having previously lived in Kyrgyzstan and, briefly, in Dagestan. Yet he was able to settle in Dagestan last year, with no apparent repercussions. He was joined there earlier this year by his wife — who has lately commented that her sons couldn’t possibly have been involved in the dastardly crime committed in Boston.

Intriguingly, though, she appears to have believed that the atrocities of September 2001 were an inside job intended to defame Muslims — an opinion evidently shared by her sons.

There are, inevitably, a host of questions at this stage, and there’s a fair chance many of them will remain unanswered, given that Tamerlan died last Friday and there are doubts whether his younger brother, Dzhokhar, who was charged on Monday with using weapons of mass destruction to cause death and damage to property, will be able to respond coherently in any interrogation.

Anecdotal evidence suggests the 19-year-old Dzhokhar wasn’t quite as alienated from his environs as the 26-year-old Tamerlan: friends have described him as laid-back and inclined to relish doses of marijuana.

The extent to which he was misled into last week’s gory misadventure by his elder brother cannot clearly be delineated at this stage, but some such stupidity is broadly deemed to be a part of the scenario.

It is somewhat gratifying that Dzhokhar, contrary to advice from some Republican legislators, ultimately was not designated as an enemy combatant. He has spent most of his life in the US, and perhaps deserves to be seen in the same light as other Americans who perpetrate acts of random violence.

A few commentators have pointed to the irony that the US Senate rejected even the mildest gun controls in the same week as the Boston bombings, even though gun violence has consistently accounted for far more deaths than acts formally designated as terrorism, and despite up to 90pc popular support for background checks on weapons purchasers.

It is perfectly reasonable for jihadist fantasies to be a cause for concern in the Boston aftermath, but surely the same goes for the culture of violence that permeates American society.

mahir.dawn@gmail.com