People react in front of the restaurant Le Carillon, one of the establishments targeted in the Paris attacks.  (AP Photo/Kamil Zihnioglu)

"War." It was one of the most-used words in the French news media in the days following the terror attacks in Paris. Earlier this week, French President Francois Hollande voiced a common sentiment among many French: "We must destroy Daesh," he said, using another name for the Islamic State.

In a YouGov poll after the Nov. 13 attacks, about three-fourths of respondents said France should intensify its airstrikes targeting the Islamic State. Nearly half  even agreed that France should send ground troops into Syria.

"Within the population, my general impression is that of initial defiance, followed by subdued soul-searching to try to make sense of things, and also by the need for life to slowly start running its course again," said Olivier de France, research director at the French Institute for International and Strategic Affairs. "Alongside this determination to get on with things, there has clearly been underlying angst and fear."

Some in France want to take their fears to the battlefield. In November, the French military had registered about 40 percent more applications than during the same period in 2014. The interest was partially sparked by the attacks on Charlie Hebdo and a Jewish supermarket in January, according to military sources cited by the French weekly Le Point. Authorities have suggested that the trend might intensify in the aftermath of attacks that caused many more deaths.

Speaking to Le Point, French military official Éric de la Presle said the rise in applications wasn't about revenge. "It is a totally new phenomenon," he said.

France's president, Francois Hollande, arrives at the airport of Timbuktu Feb. 2, 2013. (FRED DUFOUR/AFP via Getty Images)

One young man interested in becoming a soldier was quoted as saying: "The attacks from last Friday have only strengthened my opinion. Becoming a member of the military is a useful service to the country." Officials said they had even received an application 67-year-old man. He, however, had to be turned away: The maximum age for recruits is 37.

"This is quite new and echoes the patriotic sentiment in the U.S. after the 9/11 attacks," said Camille Grand, the director of French defense think tank Fondation pour la recherche stratégique. "The significant rise in volunteers for the armed and security forces is unprecedented in recent years. It is difficult to foresee whether it will last."

Others, however, are starting to question whether France is overreacting. "A few voices on the left and among liberal intellectuals are warning against a trade-off," said Grand, referring to fears that civil liberties could be curtailed. Speaking about those opposed to more military action, he said: "They represent only a small minority and a minuscule fraction of the public opinion with a very limited echo so far."

Other experts said that analysts should not forget other security challenges, apart from the Islamic State. "Al-Qaeda is still active and tries to keep its image of world-leading, specifically global jihadist organization," political scientist Julien Theron said.

The focus will remain on the Islamic State in the foreseeable future, though. "There is a more acute sense of the threat as, at least, for Parisians, everyone knows someone who has been killed, injured, who escaped miraculously or could have been a victim," Grand said.

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