Carlos Barria / Reuters

After terrorists sprayed bullets and blew themselves up in the streets of his capital, the French president vowed to “be merciless toward the barbarians of Islamic State group.”

“Terrorism will not destroy France,” Francois Hollande said after the attacks, which claimed 130 lives, “because France will destroy it.”

Hollande has embarked on a whirlwind tour this week to discuss that pledge, meeting with the leaders of the United Kingdom, the United States, Russia, Germany, and Italy to urge them to come together in  a “grand and single coalition” that transcends political disagreements. Two days after the attacks in Paris, France unleashed its biggest air raid in Syria to date, dropping 20 bombs over the Islamic State’s stronghold in Raqqa in a single night. Now, Hollande is trying to convince other nations to enhance their operations in Syria, too.

That’s easier said than done. The international consensus on the fight against the Islamic State has ballooned since the downing of a Russian airplane and attacks in Paris and Beirut—all attacks claimed by the Islamic State. But world powers each have their own reasons for fighting the world’s most violent jihadist organization—and their own strategies.

Hollande kicked off his itinerary with British Prime Minister David Cameron on Monday in Paris. By Hollande’s standards, it went well: After the talk, Cameron told reporters that he would begin making his case to his government for bombing Islamic State targets in Syria (so far, it has only hit targets in Iraq). The prime minister lost a vote in Parliament to allow air strikes there two years ago following the Assad government’s use of chemical weapons against Syrian citizens. But that was before the Islamic State emerged, and, as the Associated Press notes, the mood within the legislature has changed since then.

Hollande met with President Barack Obama on Tuesday, who pledged to support France in the fight against “a scourge that threatens all of us.” But Obama did not say the U.S. would intensify its air strikes in direct response to the Paris attacks, echoing his remarks from last week, in which he insisted the current U.S. strategy “is going to work.”

Obama’s assurances came across as largely symbolic. He said that he and Hollande have agreed “that nations must do more together” and that “we are going to keep stepping up that coordination.” Obama said that, under an agreement brokered after the attacks, Washington will share more intelligence information with Paris.

The meeting illustrated a role reversal for the U.S. and France. As Stephen Collinson and Kevin Liptak described it CNN:

A dozen years ago, it was a French President—Jacques Chirac—who was calling for restraint as George W. Bush was bristling for war with Saddam Hussein in Iraq following the September 11 attacks. And it was a French foreign minister who warned that Washington might win the war but lose the peace if it fractured Iraq.

The changing dynamic between the two old allies reflects the impact of 14 long years of war that has left America weary of foreign intervention, as well as the insistence by Obama that a rush to war after terror attacks often goes awry.

Obama was pointedly skeptical about cooperating with Russia, as Hollande has urged. Russia’s intervention in Syria has focused on rebel groups fighting against the Assad government opposed by the U.S., rather than on Islamic State targets.

“We agree that Russia could play a more constructive role if it were to shift the focus of its strike to defeating ISIL,” Obama said, using one of the acronyms for the Islamic State.

Hollande, who will travel to Moscow on Thursday, said he would tell Russian President Vladimir Putin that “France can work with Russia, if Russia concentrates the military action on Daesh,” using another name for the group.  

Russia has signaled that it is willing to work more closely with France in the campaign against the Islamic State. Last week, Putin ordered Russian naval forces to work with French warships “as allies” in attacking the Islamic State.

Any future cooperation, however, could be complicated by Turkey’s decision to shoot down a Russian warplane in Syria on Tuesday. At Turkey’s request, NATO, whose expansion in eastern Europe Putin has long and visibly resisted, will have an emergency meeting about the incident.

Hollande’s road show continues. He will meet with German Chancellor Angela Merkel on Wednesday, and with Italy’s Prime Minister on Thursday in Paris, before heading off to Moscow.

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