Games against Mexico are always special for members of the U.S. men’s national team, and Tuesday’s contest in Nashville is no different. USA-Mexico is the biggest rivalry in the CONCACAF region. The teams face off infrequently enough that every match, whether it’s a friendly or a final, feels like a big deal.

This year’s meeting takes on extra significance, though, and not just because six of the 23 players who remain on the roster haven’t faced El Tri before. It’s also the first time the two squads will face off on the anniversary of the September 11, 2001 terrorist attacks.

The USMNT has played on this date just once since 2001, beating Jamaica in a must-win qualifier six years ago in Columbus, Ohio. And with an average age of 23, many of the Americans on interim coach Dave Sarachan’s current roster are too young to remember much about the the day itself, if they remember anything at all. Forward Tim Weah, the first player in USMNT history born in the 2000s and the youngest in the current group, was 18 months old at the time.

“It’s one of those things where I wasn’t, you know, really alive,” said midfielder Weston McKennie, who was actually 3 years old. “It didn’t really have a direct effect on me, because I was a younger kid.”

McKennie learned later on about the attacks that killed almost 3,000 people in New York City, at the Pentagon just outside Washington, D.C., and in rural Pennsylvania. History was among his favorite subjects at school. He and his teammates got the ultimate lesson on the subject last Wednesday, when the team and its support staff visited the 9/11 memorial in lower Manhattan and met with firefighters, EMTs and and police officers who sprang into action on that infamous Tuesday morning.

“It’s hard to put it into words, the level of emotion and power that comes from not only the memorial, but talking to some of the first responders that were there,” said Wil Trapp, who captained the U.S. during Friday’s loss to Brazil a few miles west in East Rutherford, New Jersey. “It just awes you. We had a tough day of training, guys were tired physically, and after that you’re sapped a little bit emotionally because of just the weight of that whole memorial.”

Trapp was 8 then, and he recalls the day well. So does DeAndre Yedlin, who was in second grade. For players of Trapp’s and Yedlin’s generation, it’s their Pearl Harbor. “I remember they just kind of took everyone out of school and sent us home,” Yedlin said. “My grandpa actually grew up in Brooklyn. He had the TV on and he was just shattered, crying and everything. It was tough to see even if I didn’t really understand what was going on.”

With 53 caps, Yedlin is the most senior member of this squad. He’d actually visited the memorial on a previous USMNT trip.

“Every time you go it’s powerful, especially when you’re with members of the police department and fire department that were actually there on that day, clearing the rubble and pulling bodies out,” he said. “You hear their stories and see how emotional they’re getting. It was sad to see. It’s not a great memory. But it’s amazing to see the courage they had. Some of them were off duty, and they just drop everything and go. It’s amazing.”

Sarachan said the trip to what was once known as Ground Zero helped give the younger players who didn’t know much about 9/11 a broader perspective. As was the case on the team’s previous trips to the site, the hope is that what the players experienced will stick with them not just On Tuesday, but whenever they represent the U.S.

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“Playing on September 11, I think they came away with a whole new meaning of what went on in this country and what playing for this team is all about,” Sarachan said. The message appeared to resonate.

“It was actually pretty incredible,” added defender Matt Miazga, who was just a few days into kindergarten 17 Septembers ago. “I don’t really remember most of that day, just a few little things,” Miazga said. “It’s crazy when you‘re [at the memorial] and you see first-hand experiences. It was nice for us to go there and pay tribute and be with the NYPD and the fire department and get together and remember the people that lost their lives. Hopefully we can represent the country well.”

Added McKennie: “The sacrifices that people made, it’s what a team like us are kind of based on, sacrificing for each other, putting forth hard work and being willing to do whatever it takes to succeed.”

Doug McIntyre covers soccer for Yahoo Sports. Follow him on Twitter @ByDougMcIntyre.

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