Amid tight security, thousands marched in Paris on Saturday in commemoration of the 17 victims of two separate terrorist attacks that rocked France this week: Wednesday's massacre of 12 in and near the office of the satirical newspaper Charlie Hebdo, and Friday's siege of a Jewish grocery store that resulted in five more deaths. Appearing on Saturday in the town of Évry, south of Paris, French Prime Minister Manuel Valls told his people to expect war.

“It is a war against terrorism, against jihadism, against radical Islam, against everything that is aimed at breaking fraternity, freedom, solidarity,” he said.

Valls' choice of words—a war against terrorism—evoked almost identical language used by U.S. President George W. Bush in the aftermath of the September 11, 2001 terrorist attacks. Nine days after al-Qaeda's coordinated assault felled New York's World Trade Center and damaged The Pentagon, President Bush declined to limit American retaliation to the terrorist group.

"Our war on terror begins with al-Qaeda, but it does not end there," he declared to a joint session of Congress. "It will not end until every terrorist group of global reach has been found, stopped and defeated."

Almost immediately, Bush's broad mandate elicited criticism that the president had waged war against an abstraction. This criticism intensified in 2003, when the president justified the American invasion of Iraq in part based on purported links, later found to be false, between Saddam Hussein and al-Qaeda. In 2005, the Bush administration announced the rebranding of the "war on terrorism" to the "global struggle against violent extremism," known by the unfortunate acronym "GSAVE." It didn't catch on. The "war on terror" name lived on until 2013, when President Obama, who had withdrawn American combat troops from Iraq two years earlier, formally retired it. The Obama administration has conducted its own campaign against terrorist groups, expanding the use of drone strikes.

So why is France—a frequent critic of American foreign policy during the Bush years—endorsing, rhetorically at least, a similar approach in response to the Paris attacks? The designation likely reflects, more than anything, the country's lack of feasible options. Al-Qaeda in the Arabian Peninsula (AQAP), a group based mainly in Yemen, has claimed responsibility for the attacks. But neutralizing that group won't be easy. Under President Obama, the United States has launched several dozen drone strikes against terrorist targets within Yemen, but these attacks haven't destroyed AQAP. On the same day of the Charlie Hebdo attacks in Paris, militants from the organization reportedly executed a car bombing in Sanaa, Yemen's capital, that claimed 35 lives.

Even if France could successfully repel AQAP, the country's struggle against Islamic terrorism would be far from over. Each of the four attackers—the Koachi brothers, Ameny Coulibaly, and Hayat Boummediene, who remains at large—were born and raised in France, part of the country's Muslim population of nearly 5 million. The New York Times has reported French Interior Ministry estimates that some 1,000 French citizens were either planning to join jihadist groups in Iraq and Syria or had already done so. This trend is hardly new: According to Al Jazeera, Cherif Koachi was arrested in 2005 for attempting to travel to Damascus, from where he had planned to enter Iraq and take up arms against the United States. Later, following a stay in Yemen, Koachi came under surveillance upon his return to France. Even so, French intelligence officials were unable to prevent his attack on Wednesday.

Aside from Valls' statement in Évry, France has not yet announced how, specifically, it plans to retaliate for the Paris attacks. If the U.S. "war on terror" is any guide, France's fight is destined to be a long one.