Ten hours before the first plane hit the World Trade Center in New York City on September 11, 2001, Bill Clinton allegedly told a group of businessmen in Australia that he had a chance to kill Osama Bin Laden, but passed because it would have meant killing hundreds of innocent civilians.

That’s according to never-before-released audio of remarks made public by Australian media on Wednesday.

At the event in Melbourne, which took place not long after the end of Clinton’s term in office, the former president was asked about international terrorism.

“And I’m just saying, you know, if I were Osama bin Laden — he’s very smart guy, I’ve spent a lot of time thinking about him — and I nearly got him once,” Clinton is heard saying. “I nearly got him. And I could have killed him, but I would have to destroy a little town called Kandahar in Afghanistan and kill 300 innocent women and children, and then I would have been no better than him. And so I didn’t do it.”

White House and Pentagon officials have made it clear that obvious civilian targets are off limits — and that attacking them would not only violate international law but undermine the effort to defeat the Islamic State.

As the capital of the Islamic State’s self-declared caliphate, Raqqa holds a dense concentration of potential targets: The group’s top leaders work and live in the city, and the bureaucracy they have created to run the self-declared caliphate is based there. There are financial specialists, computer experts, field commanders and as many as 10,000 foot soldiers, and they congregate in dozens of places, including the headquarters buildings.

Raqqa’s city hall is Exhibit A in the difficulties in targeting in an urban environment. Even the most advanced and precise missiles and bombs cannot achieve the surgical precision needed to target only militants in the city hall building, American officials said.

For months, the United States military has known that the Islamic State uses the city hall in Raqqa, Syria, as an administrative center and a dormitory for scores of fighters. Some American officials even believe that Abu Bakr al-Baghdadi, the group’s leader, may have been in the building at times.

Yet, despite the American air campaign against the Islamic State, the white, three-story building remains standing because it also houses a jail. Its inmates are mainly victims of the extremist group — men caught sneaking a cigarette, women spotted with clothes that reveal even a hint of skin, shop owners who failed to pay their bills — and for American officials, the risk of killing any of them in an airstrike is too high.

The same is true of six other nearby buildings, including a mosque and court complex, which, together with city hall, compose the closest thing the Islamic State has to a headquarters.

The leaflets, which fluttered to the ground about 45 minutes before the strikes, simply said: "Get out of your trucks now, and run away from them. Warning: airstrikes are coming. Oil trucks will be destroyed. Get away from your oil trucks immediately. Do not risk your life."

"We combine these leaflet drops with very low altitude passes of some of our attack aviation, which sends a very powerful message," the colonel added.

“We want to kill terrorists, but not in a way that will help new generations of them,” said a senior American military official in Iraq.