Militant Islamist fighters wave flags as they take part in a military parade along the streets of Syria's northern Raqqa province. Thomson Reuters A Syrian native wrote two columns this week describing what day-to-day life has become in Raqqa, Syria — the de facto capital of the terrorist group ISIS.

He wrote of a city where a person's appearance could get him or her arrested if it's not in line with ISIS rules, where people are forced to attend indoctrination classes at mosques, and where residents have become so desensitized to airstrikes that they no longer bat an eye at them.

Many Syrians vowed to stay after the start of the country's civil war in 2011. For the past five years, rebels have been fighting the regime of Syrian President Bashar al-Assad, who has been known to commit atrocities against civilians as he tries to hang onto power. Jihadist groups have also moved into Syria to take advantage of the power vacuum that has opened up amid the chaos.

"For me, Raqqa was my hometown and leaving was out of the question," Marwan Hisham (who uses a pseudonym) wrote for The New York Times. "Even under bombardment, people managed to keep their businesses running. I worked two jobs."

But with ISIS (also known as the Islamic State, ISIL, or Daesh) moving in, it's become more difficult to continue with any semblance of normalcy.

"The Islamic State's capture of Raqqa in January 2014 sparked a demographic change in the city unlike any it had seen before," Hisham wrote in a separate Foreign Policy column. "Foreign fighters flocked to the city, bringing their families with them."

Those belonging to groups that aren't part of ISIS' privileged class (Sunni Muslims) were encouraged to leave the city.

"In the ugliest form of colonization, the group's members moved about, looking for houses to lodge in," Hisham wrote. "They started with Syrian regime officers' houses, homes formerly belonging to Syrian rebels, or government housing projects."

Ethnic Kurds were also largely driven from Raqqa.

"Kurds used to live side by side with their Arab neighbors in Raqqa," Hisham wrote. "But now, as the fighting between the Islamic State and the Kurdish militia known as the People's Protection Units (YPG) intensifies, they have been forced out of their homes."

Residents rest by the Euphrates River in Raqqa, eastern Syria, April 11, 2014. REUTERS/Nour Fourat

Those who agree to join ISIS can request permission from ISIS leaders to take over the abandoned homes of their former neighbors, Hisham explained.

"The Islamic State has fixed its attention on government employees' apartments," Hisham wrote. "Once it is known that an employee has moved out, the jihadis will break into the apartment and claim everything inside it. If the owner doesn't show up in person to reclaim his possessions — and who would? — all belongings are transferred to the new occupant selected by the Islamic State."

ISIS justifies these takeovers by saying that the confiscated apartments are now state-owned. Therefore, ISIS (which considers itself a legitimate state) can decide how to distribute them.

Jobs are hard to come by in Raqqa, especially for those who don't want to work for ISIS. Most government operations have shut down, and many educated people have turned to subsistence farming to feed their families, Hisham wrote in The Times.

One friend of Hisham's, Abdulrahman, is an engineer who used to work for Syria's Department of Finance before ISIS moved in. He had an apartment and a nice car, but now he "makes a meager living growing vegetables," Hisham wrote.

Because of these dire circumstances and lack of work opportunities, some turn to ISIS even if they don't agree with the group's radical ideology.

"I've seen first hand that for Raqqa's teenagers, the Islamic State's ideology has zero appeal," Hisham wrote. "What they want is its money and its guns."

And ISIS pays more than most people would be able to make otherwise. A fighter could start out earning $200 a month in Raqqa, which is more than a family needs to survive, Hisham wrote. Fighters are paid more for each wife, child, and slave he brings to the table, plus extra money for provisions. And this is all separate from the housing ISIS provides — once a fighter applies for a house, he'll typically get it in about two months.

Aside from the financial incentives, the respect and fear that comes with being an ISIS fighter appeals to some young men.

"These young men want to be listened to when they speak, and feared," Hisham wrote. "These motives — 'respect, cash and guns' — are turning ordinary young people into murderers."

There are work opportunities outside of becoming an ISIS fighter, as well. One of Hisham's acquaintances, for example, works as an accountant for ISIS' drinking-water department and earns $100 per month.

Fighters are highly valued, however. And they're dying off so quickly in battle that ISIS has now reportedly resulted to drafting people into its terror army.

"Near the front line where the Islamic State is fighting the Kurdish People's Protection Units, or YPG, the jihadists have already conscripted one man from every family," Hisham wrote. "They claim it's so they can 'defend their villages.'"

Raqqa residents have feared this happening for quite some time — Abu Ibrahim al-Raqqawi, an activist with the group Raqqa is Being Slaughtered Silently, told Business Insider in October that ISIS authorities in Raqqa started forcing males over the age of 14 to register with their militant-run government.

"There are rumors in the city that, 'Boys must not sit at home like women,'" Raqqawi said. "There is a war. They need to go to jihad.'"

Islamic State billboards are seen along a street in Raqqa, eastern Syria, which is controlled by the Islamic State, October 29, 2014. The billboard, right, reads: "We will win despite the global coalition." REUTERS/Nour Fourat

ISIS is reportedly preparing to defend its hold on Raqqa from an upcoming assault led by the YPG and other anti-ISIS, anti-Assad rebels.

As a US-led coalition and local rebels prepare for a fight to take Raqqa back from ISIS, airstrikes have become a nightly routine in the city, Hisham wrote.

"When the jet fighters interrupt, all eyes turn to the sky," Hisham wrote in Foreign Policy. "Everything here is a target, because the Islamic State is everywhere. But once the bombs are dropped, people go back to what they were doing. It's no longer a moment of reflection about life and death, nor a moment of curiosity about what happened: It's something that has no ending."

Hisham described how locals are victimized by both western airstrikes and by ISIS itself. The group has implemented strict rules in its "caliphate," the territory it controls in Iraq and Syria, and breaking them could mean public whippings, being forced to attend indoctrination courses on ISIS' version of Sharia law, or worse.

"The Islamic State used any excuse to preach their ideology to Raqqa residents," Hisham wrote. "You could be a poor person who asked for zakat, the money taken from the rich as alms, without first registering with the Islamic State, or a government employee who studied in the Assad regime's schools and therefore have a 'non-Islamic education,' or a graduate of a 'secular law' school — all are forced to submit to indoctrination."

Other offenses include not dressing according to ISIS rules (veils for women and long beards for men).

Some lawbreakers are forced to dig trenches around the city, which exposes them to airstrikes.

Hisham concluded his Times column by offering advice on what could put an end to ISIS' reign of terror in the Middle East and across the world.

"The people under this occupation present the best hope for destroying the jihadists," he wrote. "Without their support, the Islamic State can hardly be defeated."