NEW ORLEANS (AP) — A thrilling finish. A huge upset. Indeed, America got a Super Bowl that was worth all the fuss.

The outside of the Superdome looked more like a military compound than a football stadium Sunday, complete with soldiers on the ground and sharpshooters on the roof.

But the real action came inside, where Adam Vinatieri kicked a 48-yard field goal with no time left to lift the New England Patriots to a heartstopping 20-17 victory over the St. Louis Rams.

The most secure NFL title game ever was also an old-fashioned thriller that lived up to the hype — a shocking upset, a true testament to why football is the country’s favorite sport.

And of course, with a game awash in flag waving, nobody could overlook the nickname of the winner — the Patriots, a 14-point underdog who went 5-11 in 2000 and weren’t picked to do much better this season.

“We’re all Patriots, and tonight, the Patriots are world champions,” New England owner Robert Kraft said.

Vinatieri’s game-winner will look great on his resume, above even the 45-yarder he kicked in the snow to send New England’s first playoff game into overtime.

“He’s been dependable and he’s been our clutch guy all year,” Patriots coach Bill Belichick said.

The game-winner was set up by a 53-yard drive engineered over the final 1:21 without any timeouts by Tom Brady — the quarterback who came from nowhere to replace superstar Drew Bledsoe.

“I knew they would give me the chance because we have a ton of champions,” Vinatieri said. “I’ve never been so proud to be a member of anything in my life. We shocked the world, but we didn’t shock ourselves.”

The Patriots became the biggest underdog to win since Joe Namath and the New York Jets, 18-point underdogs against the Baltimore Colts, won 16-7 in 1969.

The Patriots finally put their name on the Vince Lombardi Trophy after 42 years in existence. They had made two previous trips to the Super Bowl, both in New Orleans, but they had never seen the Big Easy in this light.

Nobody had.

It was an eye-opening spectacle — as much about military might outside as the football inside, and yet another jarring reminder of how much has changed since Sept. 11.

The pregame and halftime shows were awash in patriotism and remembrance.

The emotional peak came at halftime, when rock band U2 sang its haunting hit, “Where the Streets Have No Name,” while the names of the victims of the terrorist attacks were displayed.

But nothing could have topped the way the game ended.

“We shocked the world!” Patriots safety Lawyer Milloy said.

Ticketholders arrived up to five hours early to guarantee they wouldn’t miss the start. Lines stacked up outside the 8-foot-high fences and concrete barriers surrounding the stadium.

Fans stood in queue an hour or longer to make their way into the dome, waiting to be patted down by security guards, then getting in another line to pass through metal detectors.

On the whole, they were patient and understanding.

“But it’s sad the country has come to this,” said Ronnie Barko, a ticketholder from West Palm Beach, Fla.

There were sharpshooters walking the perimeter of the Superdome, and uniformed soldiers all over New Orleans. A no-fly zone was in effect over the stadium.

Hardly anything was easy about the Big Easy on this Super Sunday. Interstate 10 was closed to truck traffic, because the major highway runs right past the Superdome, the stadium built in the mid-1970s as a monument to big games like this one.

“It’s a sign of the times,” Patriots fan Tricia McCarthy said. “Whenever you have big crowds somewhere, you have to worry about terrorism. It’s pretty sad to say.”

The Secret Service coordinated the biggest security effort in the history of football, ensuring New Orleans would be the safest place in America on Sunday. The nation’s leaders knew there was more than a game hanging in the balance.

“We will always be alert to the possibility of a terrorist event at a high-profile event like the Super Bowl, like the Olympics,” Homeland Security Director Tom Ridge said on NBC’s “Meet the Press.”

Even more stringent measures are in place for the Olympics, which begin next week in Utah. Still, the Super Bowl was much, much more than a dress rehearsal.

The Super Bowl is the most-anticipated single sporting event in the country, an unofficial national holiday of sorts, watched by 130 million viewers last year.

Some say it’s a tribute to excess — that no game is worth this much attention. But in a way, that’s what made it even more important in the post-Sept. 11 world. Football is an entrenched symbol of American culture, and not playing the biggest football game of all was never an option.

“You can’t live in fear,” Patriots fan Calvin Brown said.

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