NEW YORK — Behind the barbed wire, the white minivan’s busted windows and crumpled roof hint at its story. But on this windblown spot on the John F. Kennedy International Airport tarmac, between a decommissioned 727 and a hangar, it’s doubtful passing drivers notice it at all.

In the long struggle with the searing memories of 9/11, though, the van’s solitary presence here marks a small but significant transition point.

Tons of wreckage — twisted steel beams weighing up to 40,000 pounds, chunks of concrete, a crushed fire engine, a dust-covered airline slipper — were salvaged from the World Trade Center site for preservation in the weeks after the 2001 terrorist attacks.

Now, 15 years later, this minivan, part of a government agency motor pool in the parking garage beneath the complex, is the very last artifact without a resting place.

When the vehicle is claimed, as soon as a few weeks from now, it will fulfill a pledge that, to move beyond 9/11 without losing sight of it, New York would share relics of that terror, along with the tales of sacrifice and fear that come with them.

The decision by officials to give away pieces of Trade Center wreckage has been praised and criticized over the years. But its impact is undeniable.

More than 2,600 artifacts have gone to 1,585 fire and police departments, schools and museums, and other nonprofit organizations in every state and at least eight other countries.

Each recipient has pledged to use them in memorials or exhibits honoring those killed on 9/11. While some have not followed through, the many that have mean it is possible to touch a piece of Sept. 11 during a Catholic Mass in Port St. Lucie, Fla., while standing in the shadows of Colorado’s San Juan mountains, or in a park honoring animals in Ontario.

‘‘They are the relics of the destruction and they have the same power in the same way as medieval relics that have the power of the saints,’’ said Harriet Senie, a professor of art history at the City University of New York and author of ‘‘Memorials to Shattered Myths: Vietnam to 9/11.’’

‘‘History is a vague concept, but if you have this tangible object that was a part of this historical event, it makes it very difficult to deny and it also makes it possible to experience it in a very visceral way.’’

President Obama on Saturday honored the nearly 3,000 souls who were lost in the Sept. 11 attacks, as well as the bravery of survivors and the emergency personnel who responded, and the work of scores of others who have labored since to keep the homeland safe.

In his weekly radio and Internet address, Obama said that while so much has changed in the years since 9/11 it’s important to remember what has stayed the same. ‘‘The core values that define us as Americans. The resilience that sustains us,’’ he said on the eve of the 15th anniversary of one of the nation’s darkest days.

He said the terrorists’ goal is to frighten Americans into changing how they live, but ‘‘Americans will never give in to fear.’’

Nearly 3,000 people were killed in New York City and Pennsylvania and at the Pentagon when hijacked commercial airliners were slammed into all three locations in attacks that were planned and carried out by Al Qaeda.

Obama said the terrorist threat has evolved since Sept. 11 ‘‘as we've seen so tragically from Boston to Chattanooga, from San Bernardino to Orlando,’’ cities that suffered terrorist-linked attacks. He pledged that the nation will stay relentless against terrorism.

In the days immediately after the attacks, it wasn’t at all clear what would happen to the wreckage of the Trade Center.

The Port Authority of New York & New Jersey, which owned the Trade Center, sent an architect to comb through the site and cull pieces that seemed distinctive.

Investigators carted away others. Most of the wreckage from the site was scrapped or recycled. But the agency saved about half of 1 percent of the total.

It ended up in JFK’s Hangar 17, an 80,000-square-foot cavern of sheet metal left empty when tenant Tower Air went out of business in 2000. A judge determined the artifacts were not evidentiary or personal, and approved donations to those who promised to care for them.

Many artifacts went to fire departments, local governments, and organizations in the New York area with direct ties to the first responders and workers who died when the towers fell.

‘‘When those buildings came down, everybody and everything in its path was either pulverized or vaporized off the face of the earth,’’ said John Hodge of the Stephen Siller Tunnels to Towers Foundation, named for his cousin, a New York firefighter killed on 9/11.

‘‘That’s where the DNA is. Neither my cousin or anybody else from Squad 1 was ever found, but it’s in that steel,’’ Hodge said.

Firefighters in Pagosa Springs, Colo., created a memorial in front of their station around a small piece of donated I-beam. Many people in the town will never get to New York or Washington, said David Hartman, who worked to obtain the artifact. But Sept. 11 was his generation’s Pearl Harbor, and being able to see and touch the wreckage enables residents to reflect on its lessons, he said.

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