OPINION: Nice attack - the wider threat to France
With the death of the driver who ploughed his truck through dozens of French civilians in Nice, it may take a while for authorities to get to the bottom of what motivated the attack. The broader picture, however, looks unpleasantly clear: mainland Europe, and France in particular, is facing a vicious, repeated string of attacks that are hard to stop and likely to produce evermore unpredictable political consequences.
In France alone, well over 200 civilians have now been killed since attackers targeted a kosher supermarket and the offices of the satirical magazine _ Charlie Hebdo_ in January 2015. And while the vast majority of deaths occurred in just three events - that killing, the assault in Paris on 13 November 2015 and now the Bastille Day truck attack in Nice - it appears that much smaller, more limited but still often deadly strikes are also on the rise.
It's not just France, of course, but for now that country appears the most at risk. According to European security officials, the 22 March Brussels attack that left 35 dead, including three perpetrators, also had been intended for French soil. In response, the country has mobilised on an almost wartime scale, with troops on the streets and a national state of emergency.
Only hours before the attack in Nice, President François Hollande had ironically announced that the state of emergency imposed after November's attacks would be lifted at the end of the month.
Progress has clearly been made - militant cells have been rounded out and perhaps more importantly, disrupted. The fact that this attack appeared to have relied on a civilian truck might imply that there has also been some success in denying those who want to conduct attacks access to more conventional weaponry.
We don't know for sure whether Thursday's attack was directly related to Islamic State or even broader Islamist radicalism - although perhaps unsurprisingly, Islamic State and other jihadi-linked social media feeds were quick to rejoice in what had happened, implying that their supporters would at least like to believe there was a link.
Even if that proves not to be the case, that will not dramatically reduce the worry for European security chiefs. What the Bastille Day attacker successfully demonstrated was just how much could be achieved with a single determined driver and large motor vehicle.
Such tactics are hardly new. Israel has seen multiple attacks using vehicles and heavy building machinery conducted by Palestinian militants, in part seen as a response to local security measures making it hard to transport bombs or firearms. The death tolls, however, have generally been much smaller: rarely more than a handful of civilian or security personnel.
This appears to have been at least the fourth politically or militant-inspired "vehicular assault" in France since 2014. Two attacks took place with motor vehicles in December 2014 in the towns of Nantes and Dijon, killing one person and injuring more than 20. In January this year, an attacker rammed four French soldiers who were guarding a mosque in Valence, although none were killed. The attacker was found to have jihadist propaganda on his computer, although it is not clear whether he was directly linked to any group.
The deadliest single attack in Europe remains the 2004 Madrid train bombings claimed by al-Qaeda that killed 192. Similar attacks on London's mass transit system the year before took another 56 lives, including those of the four suicide bombers. But that momentum, crucially, was not maintained despite multiple other attempts to blow up airliners and conduct other attacks.
The death toll in Europe remains a fraction of that in countries like Iraq, Pakistan, Syria or Afghanistan. Still, given the savagery and death toll of recent attacks, it is fair to say France is now on the receiving end of the most sustained militant assault any Western state has yet faced. (The death toll from mass shootings in the US remains substantially higher, but they are not seen as co-ordinated in the same way.)
In Europe, there are parallels with the campaigns waged by Northern Irish Republican or Spanish Basque separatists in the last three decades of the twentieth century. In total, those had death tolls that run much higher than the several hundred killed by militants in Europe since 9/11. But the individual death toll in each attack was invariably much lower, and there was never a sustained tempo of mass casualty events like that now seen by France.
Even some of the smaller attacks have had a truly brutal savagery. On 13 June, a French police officer and his wife were stabbed to death in their own home in a town outside Paris by a single attacker in an attack claimed by Islamic State. The attacker live-streamed the attack on Facebook. French officials said he appeared to be acting on a recent general order from the Islamic State leadership to attack its enemies during the holy Muslim month of Ramadan.
Such "lone wolf" attacks are much, much harder to stop.
Even before the attacks of the last two years, France was struggling with serious social divisions, particularly around the integration of residents -many of them Muslim - on underprivileged estates on the outskirts of cities. That appears to have become compounded with the West's war with Islamist militancy in general and Islamic State in particular.
Although the reality is rather more complex, it's hardly surprising recent attacks have stirred up further public discontent over migration and open borders, fueling the limited but very real rise of Marine le Pen's National Front. With presidential elections due in April and May next year, Hollande badly needs to look like he has a grip on the problem.
Whether that's something that is genuinely possible, unfortunately, is a rather different question.
Peter Apps is Reuters global affairs columnist, writing on international affairs, globalisation, conflict and other issues. He is founder and executive director of the Project for Study of the 21st Century (PS21), a non-national, non-partisan, non-ideological think tank in London, New York and Washington.