The French military launched more airstrikes against the Islamic State in Raqqa, Syria, on Nov. 17, 2015. The strikes involved 10 jets launched from Jordan and the Persian Gulf, and targeted training and command centers. (YouTube/France Forces)

Despite heavy French bombardment of the Islamic State’s self-proclaimed capital of Raqqa this week, damage to the extremist group appears to be minimal, according to analysts and Syrian activists.

The airstrikes — retaliation for last Friday’s attacks in Paris claimed by the Islamic State — hit such targets as a command post and a militant-training center in and around the Syrian city, French officials said.

But after more than a year of U.S.-led coalition airstrikes, the ­Islamic State has learned to secure its weapons, communications systems and fighters in fortified bunkers or densely populated residential areas where bombing would inflict intolerably high civilian casualties, analysts and activists said.

The French attacks highlight a limitation of air power, said Theodore Karasik, a Dubai-based expert on military issues in the Middle East. Rarely is that approach capable of subduing enemies, he said.

What started out as simple protests in Syria has expanded to civil war and now an international crisis.

“The Islamic State, like any other terrorist group, has adapted and developed its own underground networks in order to safeguard their prized assets,” Karasik said. “Airstrikes can be effective, but you need a ground component to go along with them.”

Raqqa, a city of about 200,000 people in eastern Syria, fell to the Islamic State in 2014 and has come under air bombardment by multiple countries as well as the Syrian government. The city is the symbolic heart of the extremist group’s self-declared caliphate and home to senior leaders in the group, analysts say.

The U.S.-led coalition has attacked the group in its strongholds in eastern Syria and northern Iraq for more than a year.

Russia, which in September ­began airstrikes against armed opponents of Syrian President Bashar al-Assad’s government, also conducted air attacks on the city Tuesday. Russia, which does not coordinate its attacks in Syria with the U.S.-led coalition, last month carried out airstrikes on Raqqa that killed as many as 27 civilians, according to the Britain-based Syrian Observatory for Human Rights.

The monitoring group said that more than 30 Islamic State fighters in Raqqa have been killed in airstrikes in recent days and that family members of the group’s leaders have left the city.

Although obtaining information from the city is difficult, Syrian activists say the French air raids this week did not kill civilians. But neither did the attacks deliver crippling blows to the Islamic State’s leadership or defenses in the city, said an activist from Raqqa Is Being Slaughtered Silently, a monitoring group opposed to the Islamic State.

Scores of hostages, including Westerners, have been killed by the Islamic State since 2014.

The activist, who uses a nom de guerre, AbdAlaziz Alhamza, said France and the others in the coalition appear to be aware that the militant group uses human shields to protect its fighters and operations centers in the city, including a command-like facility with an underground prison. As a result, he said, such places have not been targeted.

The Obama administration has ruled out deploying a significant ground force in Syria, whose civil war has killed more than 250,000 people and displaced millions.

The White House lacks the local allies in Syria to wage significant land battles against the Islamic State. Washington’s plan to train Syrians to fight the group has run into continued problems, while myriad issues have dissuaded a U.S.-backed Kurdish-led force in northern Syria from attacking Raqqa.

Last month, the White House said it would deploy fewer than 50 Special Operations advisers to aid the Kurdish-led force in northern Syria. The U.S.-led coalition also appears to be lowering the threshold for airstrikes by targeting the economic lifeblood of the Islamic State: oil infrastructure.

This week, U.S. officials said coalition aircraft struck more than 100 oil tank trucks in eastern Syria that were under Islamic State control. Some estimates put black-market oil sales at nearly half the group’s revenue.

But impoverished civilians run much of the group’s oil operation, including driving tank trucks, said Hassan Hassan, co-author of the book “ISIS: Inside the Army of Terror” and an analyst at Chatham House, a London-based think tank. If the drivers were not killed by coalition attacks, the destruction of the vehicles would still be an economic loss for their families, which live in places such as Raqqa.

Peter Cook, a Pentagon spokesman, said Tuesday that the strikes on the oil vehicles did not appear to have killed civilians.

“When airstrikes target things like these trucks, not only are you likely killing civilians, you’re also affecting the livelihood of these civilians’ families,” Hassan said.

Poverty, he added, is an important recruitment tool for the Islamic State.

Poverty may be worsening in places such as Raqqa, partly as a result of recent battlefield setbacks for the Islamic State, said Columb Strack, a Middle East analyst at Jane’s Information Group.

He said the group recently appears to have reduced the salaries of its fighters, from about $400 a month to $300. It also has increased taxes on industries such as agriculture, he said.

“They are coming under increasing economic pressure and passing this down on the population,” Strack said.

A more immediate impact of the air raids on Raqqa is a crackdown on residents by the Islamic State, said Abu Issa, a leader of an anti-Islamic State rebel group ­allied with Kurdish forces in an area just north of Raqqa.

Contacts in Raqqa say the group has erected scores of checkpoints in and around the city since the French attacks began, preventing residents from leaving, he said. Abu Issa expressed concern over increasingly brutal treatment, including public executions, of those suspected of collaborating against the Islamic State.

“The airstrikes are political theater, and it’s the people who suffer” in Raqqa, he said, speaking by Skype.

Sam Alrefaie in Beirut contributed to this report.

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