NYPD Commissioner William Bratton spoke from the World Trade Center memorial site in lower Manhattan about the war on terror that he said may never end.

In interviews with several Sunday morning news shows less than a week before he retires, Bratton said that ISIS, with its growing capabilities aided by technology, has become a much more formidable enemy than the Islamic terrorist group al-Qaida, which was responsible for the series of four coordinated terrorist attacks 15 years ago on Sept. 11.

Bratton reflected on the attacks before the memorial service for the nearly 3,000 victims began at Ground Zero.

The probability of another devastating attack hitting New York is high, Bratton said, despite what he said are the ever-increasing capabilities of police and other authorities to gather intelligence about and respond to terrorism.

“There’s probably no city in America or the world that has as much capacity and capability as we have in New York,” Bratton said on “Eyewitness News This Morning.”

But he told CNN’s “New Day Sunday”, “From our perspective the possibility remains high [of another attack] — not necessarily in the near term, but this is not something that is going to end today, next month or next year.”

“This is something that’s going to continue through our lifetimes and possibly into the lifetimes of our children,” Bratton said. “It’s the nature of it.”

Bratton said “the enabling, the inspiring, the directing” of terrorists since ISIS came into the picture are all capacities and capabilities “that have made this a very different set of initiatives that policing, and certainly federal government law enforcement, has to deal with.”

Asked if there were any current threats to New York, Bratton said there were none, though the situation could always change.

“There are no credible threats directed against this day or this event in New York City,” Bratton said, referring to the official 9/11 memorial ceremony, but he said an attack could happen “at any given time.”

Bratton said New York City receives threats constantly.

“We’re dealing with a constant stream of threats — some real and some imagined — to create the threat that they’re coming after us all the time,” Bratton said. He said the terrorism world is a “constantly changing landscape,” but added New York City authorities are prepared to respond to any attacks “very quickly, very forcefully and very effectively.”

Asked by “Sunday Today” in New York what people should do in the face of the ongoing terror threat, Bratton said everyone had to just live their lives as normally as possible.

“People should go about living their lives free of fear,” Bratton said. “We want them to be aware — that’s the nature of the world we live in.”

Bratton noted, however, that, “For 15 years we’ve kept this city safe” and there has not been a successful attack. 

“If we live in fear then they have won and we have lost,” Bratton said.

Lou Young of “CBS New Sunday” asked Bratton, “Are we looking here [at the 9/11 Memorial] at history, current events or a combination of both?”

Bratton said both the past and present are involved.

“We’re here to remember the history here but we’re also reminded of the history to come — the uncertainty of that as it relates to terrorism because we clearly know that the world changed on 9/11.”