Massacres attributed to the ­Islamic State have struck on four continents this year, reflecting how the appeal of the group’s ideology is growing even as the territory it controls in Iraq and Syria has receded, according to experts.
The slaughter of civilians in three large attacks in the past week alone — in Istanbul on Tuesday, in Dhaka, Bangladesh, on Friday, and in Baghdad on Sunday — suggests that militant actions beyond the caliphate’s borders are taking place more frequently and not necessarily with any overt direction from some caliphate headquarters. Even more alarmingly, a growing number of attacks, starting with those in Paris and Brussels, were conducted by gangs of assailants instead of by an individual gunman.
“What’s striking to me about the Istanbul and Dhaka attacks is that both weren’t done by lone wolves at all,” said Bruce Riedel, a former CIA counterterrorism official and analyst of al-Qaeda and the Islamic State who is at the Brookings Institution. “These were done by teams of terrorists working with a very thought-through attack plan. I call them ‘wolf pack’ attacks. They are rapidly becoming the Islamic State’s signature.”
A State Department spokesman said late Sunday in Washington that officials had heard reports of an explosion in Jiddah, Saudi Arabia, and were working with Saudi authorities to gather more information.

Deadly bombings in Baghdad

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Bombings in the Iraqi capital have killed at least 120 people. (Reuters)
Last week, to mark the two-year anniversary of its self-
declared caliphate, the Islamic State created a chart showing its influence, stretching from the moderate control it claims in the Philippines to a “covert” presence in France, with 15 other countries in between. Even countries not on the list are fearful. In India, the government says dozens of Indian Muslims are being monitored after they have undergone some kind of training with the Islamic State, but Indian officials acknowledge the actual number may be much higher.
While the core of the caliphate in Iraq and Syria has been pummeled by coalition airstrikes and by armies and militias fighting them on the ground, Islamic State soldiers have spread throughout the Middle East and far afield. Attacks in Turkey, Bangladesh, Nigeria, Afghanistan, Libya, Tunisia, Saudi Arabia, Egypt, Kuwait and several European capitals, and the lone-wolf attacks in Orlando and San Bernardino, show the Islamic State’s potency as an ideology.
Rep. Adam B. Schiff (D-Calif.), the ranking Democrat on the House Permanent Select Committee on Intelligence, said on CBS’s “Face the Nation” Sunday that the Islamic State is “vicious and adaptive” in what he called a “global terrorism campaign.”
“It’s very much losing territory, but at the same time, expanding its global presence,” he said.
U.S. intelligence officials say battlefield setbacks in Iraq and Syria appear to have driven the Islamic State’s leaders to speed up their timeline for attacks abroad. Many intelligence officials and terrorism experts think that recent terrorist strikes in Paris, Brussels, Turkey and Bangladesh are a reflection of that strategy.
“We judge that [the Islamic State] will intensify its global terror campaign to maintain its dominance of the global terrorism agenda,” CIA Director John Brennan said in testimony before the Senate last month.