Paris - The terrorist threat against Europe has mutated in the last half-decade as jihadist groups have seen their Middle East sanctuaries eroded, but analysts say the West must remain braced for more attacks.
Both Al-Qaeda and the Islamic State group -- together responsible for the highest-profile and most horrific terror attacks of the past two decades -- have lost potency as global organisations.
Despite splintering into branches and franchises, their murderous ideology is still able to inspire individuals to carry out random attacks in their name.
On Wednesday, 14 people went on trial in Paris over the massacres in January 2015 at satirical magazine Charlie Hebdo, and the murder of a policewoman and hostages in a Jewish supermarket -- violence claimed by both IS and Al-Qaeda.
The murderous shooting spree heralded an unprecedented wave of attacks in France.
The deadliest were the coordinated attacks in Paris on November 13 that year at the Bataclan music hall and other venues, when gunmen killed 130 in a plan stemming from the IS group's core leadership in Syria.
Experts believe the same style of assault would be unlikely to recur now, not least because IS has seen a dramatic loss of its territory and membership in Iraq and Syria.
This year, incidents have been more typically carried out by "isolated individuals who were not spotted by the intelligence services... and their limited or even non-existent contacts with identified jihadist networks," a source in the French anti-terror prosecutors' office told AFP.
Since 2015, France has seen 17 crimes classified as acts of terror.
Three took place in 2020, none of which were claimed by the terror groups, but were instead perpetrated by isolated individuals suffering from psychological problems.
But anti-terror prosecutors still see signs of operational coordination, including "networks of false documents and funding," the source said.
The risk of terror attacks in France remains "extremely high", Interior Minister Gerald Darmanin said Monday, adding that 8,132 people were on a national database of Islamist radicals seen as a security risk.
- 'Attack possible' -
Seth Jones, director of the Transnational Threats Project at the Center for Strategic and International Studies (CSIS) in Washington, said that in recent years, US and other military operations had "decimated" the IS external operations network, killing or capturing many of its key operational leaders.
Its military rout and the loss of territory IS had declared as a caliphate in Iraq and Syria have also diminished its status, and the motivation for individuals to carry out attacks in its name.
It remains possible that Al-Qaeda could carry out a major attack in Europe, Jones said, either directly or through individuals inspired by its ideology, though this was "not a high probability".
The coronavirus pandemic may have taken some focus off terrorism for security forces worldwide.
But it has also complicated the task of the jihadists, who have been active on a local level, but very cautious about operating further afield.
"In general, the short-term terrorist threat has risen in conflict zones and fallen in non-conflict zones," a UN report said in mid-July.
- 'Easier in Africa' -
German authorities said in April they had foiled a plot to target American military installations, and arrested five Tajiks suspected of acting in the name of IS.
Another source of risk comes from individuals released from jail in Europe or freed or escaped from Kurdish-controlled prisons in northern Syria where they have been held since IS was defeated.
Jean-Charles Brisard, head of the France-based Center for the Analysis of Terrorism (CAT), told AFP he did not rule out new targeted action by IS, pointing to recent attacks foiled in Europe.
"The next cycle will be that of those who are leaving jail," he said.
The CAT has established that 60 percent of prisoners in France convicted for their actions in past conflicts in Bosnia, Iraq or Afghanistan reoffended violently after their release.
A French security source, who asked not to be named, said West Africa is a particular concern after France's forces deployed in the region in June killed the head of Al-Qaeda in the Islamic Maghreb (AQIM), Abdelmalek Droukdel.
Eight people, including six young French aid workers, were killed in a suspected jihadist raid on August 9 in Niger, but no group has claimed responsibility for the attack.
"I find it more likely that AQIM will conduct a revenge attack against French forces or other French targets in Africa -- including North and West Africa -- than in France itself," said Jones.
"It is easier for the group to operate in Africa."
By Didier Lauras
Charlie Hebdo attacks