Paul Bradbury, then the facilities engineering manager at the Portland Jetport, was in a staff meeting the morning the first plane crashed into the World Trade Center on Sept. 11, 2001. When the second plane hit, everyone in aviation knew it was some form of terrorism, Bradbury said.

In the days that followed, details emerged. The world learned that Mohamed Atta and Abdulaziz al-Omari came to Portland, stayed at the Comfort Inn in South Portland, bought gas at a local Exxon, took some cash out of ATMs, stopped at Walmart and dined at a Pizza Hut.

Then they left their rental car at the Jetport parking lot and boarded a US Airways Express flight into Logan Airport in Boston, where they boarded the plane they would turn into a weapon.

They exploited a weakness in American society, the common wisdom that people should comply during a hijacking, mugging or robbery.

U.S. aviation essentially was shut down for about two weeks. When flights resumed, things were changed in Portland and across the country.

“When we reopened, we’d taken this huge mental and psychological hit, so part of the recovery was psychological, too. We had National Guard at the airports with machine guns,” said Bradbury.

There were changes to security, he said, lasting changes that work in layers. The cockpit doors are hardened in planes, making it impossible to reach the pilots. There are more air marshals on flights. Security has increased at airports such as the Jetport.

It’s a vigilance that’s nationwide, and not just in aviation. And because terrorists came through little Portland, Maine, there’s a recognition that we’re connected to a bigger world, suggested Richard Murphy, first assistant U.S. attorney for Maine.

“This area can serve as a transit,” said Murphy. “For that reason, we need to be on guard.”

The city and state have an active and wide seacoast, not to mention an international border, Murphy noted. Law enforcement at the local, state and federal level has communicated more since 9/11, pooling information, Murphy said.

The Coast Guard readily shares information about possible threats with local authorities and even private parties, and people in Portland Harbor remain aware, he said.

But physically, a walk through the city’s streets isn’t different today than it was 10 years ago — at least not for any reason linked to increased security post-9/11, Murphy said. While some cities such as Washington or New York may have changed, that’s not the case in Portland.

‘New Mainers’

One of the things that has been happening in Portland in the last 10 years is a demographic shift. Census numbers over the past decade tell the story. In 2000, the city had 64,249 residents; 91.3 percent were white and 2.6 percent were black.

In 2010, there were 66,194 residents. According to the census, 85 percent were white, and the number of blacks had doubled to 7 percent.

People who work with the immigrant community said that jump has to be because of an increase in refugees from African communities who came here directly or from other states.

“This is really, in a way, the picture of immigration — they are the new Mainers,” said Reza Jalali, coordinator of multicultural student affairs at the University of Southern Maine. Catholic Charities initially helped settle refugee families in Portland. Other refugee families around the country moved here to be near their relatives, attracted by the relative safety of Maine as well as the natural beauty and potential for work, he said.

But 9/11 also played a role in the growth, Jalali suggested.

Jalali, a native of Iran who has been in Maine since 1985, co-authored a book in 2009, “New Mainers,” which told the stories of 29 immigrants in the state from various backgrounds and nationalities.

“If you lived in a state that was intolerant, you packed up and left,” he said. “Vice versa, if you found a state that was tolerant, you were likely to move there. We were one of those that gained.

“I would even dare to say it’s because of the anti-Muslim, anti-Arab feeling that we began to gain — because Maine is more tolerant.”

There is a sense in Maine, he suggested, that people don’t really care who you are, what you look like or where you came from, as long as you don’t bother them. Put simply, it’s a live-and-let-live attitude.

That’s attractive, particularly to refugees who often had been sought out and persecuted in their homelands.

Jalali can point to the changes in Portland. He sees not only a greater immigrant population, but a greater diversity in the countries represented — Morocco, Libya, Algeria, Iraq, Iran, Sudan, Somalia, Lebanon, Tunisia, Saudi Arabia, Egypt, Ghana, Nigeria, Kuwait, Burundi, Cambodia, Malaysia, India, Uzbekistan and Bosnia, to name a few.

Ten years ago, there was one mosque in Maine, in Portland. Now there are eight — one in Orono, one in Augusta, two in Lewiston and four in Portland. At a recent Eid celebration in Portland, 2,400 Muslims came to worship.

By his research, Jalali figures there are between 8,000 and 10,000 Muslims in Maine, compared with 10 years ago, when there were maybe 1,500 to 2,000 — and many of them are in Portland.

“I think Portland has really shown, in post-9/11 years, what a remarkable place it is,” said Zachary Heiden, legal director of the Maine Civil Liberties Union. “At a time when racial profiling and discrimination against Muslim Americans as well as Arabs and South Asians has been on the rise, both officially and unofficially, Portland has stood out as a place that’s welcoming.”

Heiden wondered what the next 10 years would bring — whether Portland would become more like other parts of the country, where discrimination against Muslims, he said, was on the rise.

“What I hope will happen is that other parts of the country will take Portland as an example, and we’ll see how diverse communities can live together peacefully and respectfully,” said Heiden.