By Jay Levine

CHICAGO (CBS) — At a counter-terrorism conference in Chicago on Tuesday, Fire Commissioner Jose Santiago said it is no longer a question of if there will be a terrorist attack on Chicago, but when.

Chicago has been the target of nearly two dozen terror plots, from Hamas, to al Qaeda and Islamic State, CBS 2 Chief Correspondent Jay Levine reports.

Police Supt. Garry McCarthy said much has changed since the 9/11 terrorist attacks, with better coordination between first responders.

“They’ve come a long way, too, the bad guys. What we have to look at is how do we respond to these incidents versus how we have in the past,” he said.

But Marvin Zonis of the University of Chicago says authorities still aren’t perfect.

“There is still a whole problem of silos where whole host of organizations not sharing their findings with other organizations,” he said.

Almost immediately after the Sept. 11 attacks, authorities tried to tighten borders and increase scrutiny on those coming and going.

Less than a year later, Jose Padilla was arrested at O’Hare as he returned from Iraq.

He was linked to al Qaeda and has planning to build and detonate a dirty bomb. He’s now serving a 21-year prison term.

Some credit the lack of terrorist attacks here to a more inclusive attitude toward all Muslims.

“When Muslims feel part of American society, they’re more likely to report suspicious behavior on the part of other Muslims,” said Zonas. “That’s very important.”

In 2004, Muhammad Salah of Bridgeview was charged with laundering money for Hamas, but was acquitted of most charges and ultimately removed from the terrorist watch list.

In 2009, David Headley’s link to Pakistani terrorists and the deadly hotel attack in Mumbai, India led to his arrest at O’Hare as he boarded a plane for Pakistan.

He was sentenced to federal prison for 35 years.

The deadly Boston Marathon bombing allegedly motivated Sami Hassoun to plan the backpack bombing of Wrigley Field, during a Dave Matthews Band concert.

Hassoun’s motives had nothing to do with international terrorism; he simply wanted to shake up the local political landscape.

He’s now serving 23 years in prison.

Both Hassoun and Adel Daoud had their plots infiltrated by the FBI. Daoud was arrested after planting what he thought was a car bomb outside a South Loop liquor store.

He’s still awaiting trial.

So are the Edmonds brothers; 1 arrested at O’Hare, the other at home in Aurora

The are both accused of plotting to travel to join ISIS in Syria.

Mohammad Hamzah Khan of Bolingbrook was also arrested at O’Hare last year as he was leaving to join ISIS.

He’s currently negotiating to plead guilty in federal court.

Attorney Thomas Anthony Durkin says zero tolerance may have snared some innocent suspects.

“If you promise to stop everything, you have to err on the side of stopping everyone and there are plenty of goofy people talking about goofy things on the Internet. Does that make them a potential terrorist? In my experience I think, it does not.”