France has been one of the strongest voices pushing for the removal of Syrian President Bashar Assad, but the past four years have seen its strategy fail and its diplomatic weakness exposed.

"At its heart, it's a story of missed opportunities," said a government source, speaking on condition of anonymity.

Several Eastern European countries are becoming increasingly worried that the West may abandon Ukraine in return for Russian backing in Syria, as Paris, Moscow and Washington develop closer ties in the fight against the Islamic State jihadist group.

The three Baltic states, which were under Moscow's thumb until 1991, were particularly spooked by Russia's annexation of Crimea from Ukraine last year and are concerned about the Kremlin's territorial ambitions.

A fireman of Algerian origin, Faisal helped evacuate thousands from the Stade de France during the Paris attacks, guiding panicked football fans to safety as suicide bombers blew themselves up outside.

Now he fears the November 13 massacre across the French capital will deepen a dangerous "them and us" schism between France's five-million-strong Muslim population and the rest of society.

On the outskirts of the Syrian Christian town of Sadad, children play in front of a cannon fired just hours ago in an ongoing battle against the Islamic State group.

Soldiers and pro-regime militiamen nearby look on with amusement at the children, who appear oblivious to the fact that their ancient town is now in the sights of the jihadist group.

United by the trauma of terrorism, 14 years apart, New York and Paris have exhibited the same fortitude and determination to overcome the tears and fears with love, life and laughter.

Experts say this is the best possible response to such horrors.

The family homes of the suspected mastermind of the Paris attacks and one of the suicide bombers stand only a few blocks apart in the Belgian capital's Molenbeek neighborhood. After a string of attacks in recent years linked to its grimy streets in central Brussels, a key question arises: Why Belgium?

The tiny nation renowned for beer, chocolates and the comic book hero Tintin is now suddenly infamous for Islamic extremism — and the easy availability of illegal weapons.

More armed police are to be deployed in London after the Paris attacks, but the move is unlikely to herald a shift toward providing weapons to most officers in the largely unarmed British force, experts said.

Britain is proud of being one of few countries where police usually do not carry guns, and the sight of heavily armed counter-terrorism police officers in recent days is highly unusual one for many people.

Western powers must ramp up air strikes by 10 to 20 times to have any hope of disrupting the Islamic State group, which risks turning Europe into an urban guerrilla warzone, warned one of the world's leading counter-terrorism experts.

David Kilcullen, an Australian army veteran, became the senior counter-insurgency adviser to U.S. General David Petraeus during the Iraq War and is considered a key architect of the "Awakening" strategy that helped turn the conflict around.

Ten years after she took office, German Chancellor Angela Merkel stands alone as the leader of a European Union that is grappling with multiple crises, despite the fact she has been weakened domestically, analysts say.

Merkel's trailblazing decision to welcome refugees during the migration crisis came after she led the European Union's response to the Ukraine conflict and helped keep Greece in the eurozone.

The tide of global rage against the Islamic State group lends greater urgency to ending the jihadis' ability to operate at will from a base in war-torn Syria. That momentum could also force a reevaluation of what to do about President Bashar Assad and puts a renewed focus on the position of his key patrons, Russia and Iran.

The Syrian leader has lost much of the country to IS and other groups in the four-year war; half the population has been displaced, many areas have been leveled, and masses of refugees are flooding Europe. Along the way, Assad's brutal military response has made him persona non grata in most of the world.