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The attacks seemed to come one after another: 130 dead on the floor of the Bataclan concert hall and on the streets of Paris. Eighty-six mowed down on Nice's historic promenade. Twenty-two people, many of them teenage girls, killed at an Ariana Grande concert in Manchester.

Since the lightning rise of ISIS in 2014, law enforcement has scrambled to stop an endless array of plots. It is only now, more than four years after Abu Bakr al-Baghdadi declared his caliphate, that the cadence has finally slowed.

ISIS attacks in the West fell steeply in 2018 compared with the previous four years, the first time the number has fallen since 2014. But the number of attempted attacks remained steady, suggesting that the group remains committed to carrying out catastrophic harm.

The difference, analysts say, is that law enforcement is increasingly foiling the plots.

ISIS remains the world's deadliest terrorist organization, and its attacks are on the rise in places like Afghanistan and Iraq. But in the West, not only has the number of attacks plummeted, but the devastation inflicted by each has also declined.

ISIS carried out 14 successful attacks in Europe and North America in 2015, 22 in 2016 and 27 in 2017, according to data collected by George Washington University's Program on Extremism. But in the first eight months of this year, it carried out only four.

"It's an absolutely dramatic dip," said the program's director, Lorenzo Vidino.

The scale of attacks has also fallen. The largest toll in a single attack fell from 130 in 2015 to 86 in 2016 to 22 at the pop concert in Manchester in 2017. So far in 2018, the worst single-day toll was in the aisles of a supermarket in Trèbes, France, where a man acting in the name of ISIS gunned down three people in March.

ISIS has lost 99 percent of the land it once held in Iraq and Syria, and the fight to evict it from the last vestige started this week. Some analysts have linked the drop in activity to the loss of territory.

But the number of attempted attacks in Europe has remained unchanged, according to data collected by the Center for the Analysis of Terrorism in Paris. That data suggest that while ISIS' capacity may have been diminished, its effort has not.

"We are able to conclude that there is no correlation between their military setbacks and the loss of territory and the intensity of the threat," said Jean-Charles Brisard, the director of the Paris-based center. "Even if the Islamic State is losing both militarily and in terms of terrain, the ideology of ISIS remains present in the hearts of individuals who want to harm us."