PARIS (AFP) - Long before being targeted in Wednesday's massacre in Paris, satirical newspaper Charlie Hebdo had been considered high on the potential hit-list for Islamic radicals calling for strikes in the heart of Europe.
When Charlie Hebdo defiantly republished already controversial cartoons of the Prophet Mohammed considered sacrilegious by Muslims in 2006, it knew it was taking a risk.
After it ran new cartoons of the prophet in November 2011, the payback started.
The weekly was fire-bombed and its website was hacked. But staff refused to be cowed and upped the ante still further the following year with a set of cartoons that included Mohammed in the nude - guaranteed to offend millions of Muslims.
In 2013, its editor-in-chief Stephane Charbonnier - one of those killed Wednesday - appeared on a "Wanted Dead or Alive" list published in Al-Qaeda's magazine, Inspire.
"Charlie Hebdo became a symbol," said Louis Caprioli, former head of counter-terrorism at France's DST intelligence agency.
"They never forgot nor forgave what they considered a supreme insult. The choice of this target is highly symbolic: they targeted secularists who dared to mock the prophet. In their eyes, it's divine vengeance."
While Charlie Hebdo's uncompromising stance against censorship won many supporters in Europe, Wednesday's attack demonstrates that its staff may have underestimated the scale of the danger.
"This attack is designed to show the ability to strike at targets that were blase and sarcastic about the potential threat to them," said Matthew Henman, of IHS Jane's Terrorism and Insurgency Centre in London.
"It's increasingly clear there are radical Islamists out there who are able and willing to take action to remedy perceived insults to Islam."
Although the satirical newspaper and its editor-in-chief had police protection, it still represented a relatively soft target to determined attackers armed with automatic rifles.
"Historically, we have seen many attacks on cultural targets," said Raffaello Pantucci, a terrorism expert at the Royal United Services Institute in London, citing the threats against author Salman Rushdie and a firebomb attack against the London publisher of a book about the child bride of Mohammed in 2008.
"Any target that is defined as the enemy is legitimate, and these sort of targets are less protected than police stations or military bases."
FRANCE AS PRIME TARGET
There are conflicting reports about which group the three gunmen may have represented and there has yet to be a clear claim of responsibility.
But it was clear from video shot by eyewitnesses that the men, armed with Kalashnikov rifles, were calm and professional, suggesting they may have had training.
France itself is seen as increasingly a top target for Islamic militants seeking to strike the West.
It has been involved in the US-led air campaign against the Islamic State in Iraq and Syria group (ISIS) since September, and France was singled out in the militant organisation's call on supporters to mount "lone wolf" attacks late last year.
Experts say that the attacks could, alternatively, be an effort by Al-Qaeda to win back the spotlight from ISIS.
"It's perfectly possible that this could be Al-Qaeda trying to regain attention - they have been calling for this sort of thing for a long time," said Pantucci.
"Ever since the gunmen attacks in Mumbai in 2008, many groups have been asking how they could copy them. There are relatively low requirements - you just need men with guns, set them loose in the urban environment and cause chaos."
France's secular policies at home and military operations in Africa have also also angered the militant community.
"France has come under a lot of fire from jihadists for its ban on the Muslim veil and its increasingly proactive role in international affairs, particularly in Mali and to a lesser extent the Central African Republic," said Henman.
French forces took the lead in combating Islamist extremists that had seized large swathes of Mali in 2013 and still has 3,000 troops deployed in the Sahel region. They are also a key part of peace-keeping efforts in CAR where Christians and Muslims have violently clashed over the past two years.
France also has Europe's largest Muslim population. Around 1,000 people from that community have travelled to Iraq and Syria to join the jihad, raising fears they could return home to sow terror.
"The question now is whether this is an isolated operation," said Caprioli.
"Are we entering a new stage with a cell that is going into action? Is a cycle of attacks coming?
"What is clear is that these killers must be found, and fast."