Recalling these events and their meaning for American society is, of course, appropriate, but you could make a slight amendment to that phrase: "We Cannot Forget" would work, as well.
Like every other American institution, baseball was altered by the terrorist attacks. The national pastime was flourishing on Sept. 10, 2001, with pennant races rolling and home run records being pursued. It was the stretch drive, the culmination of five-plus months of hopes and aspirations, the best time of the season for the teams and individuals still in the hunt.
The Yankees were being dominant as usual, but the Mariners were on their way to a record 116 victories. The Cardinals and Astros were in a red-hot race in the National League Central, and the Arizona Diamondbacks were showing distinct signs of their winning capabilities behind the pitching of Randy Johnson and Curt Schilling. Barry Bonds was moving toward a single-season home run record. The season had the requisite drama and the compelling mix of individual and group achievement.
And then, everything changed and everything stopped.
The baseball owners were scheduled to meet late in the morning of Sept. 11, in Milwaukee at the Pfister Hotel. Just before that, the Commissioner of baseball, Bud Selig, was at his suburban home, going through his daily morning ritual of riding his exercise bike while watching television news and/or sports. What he saw was what we all eventually saw: two planes crashing into the Twin Towers of the World Trade Center.
Americans shared something in those next moments. We would be shocked, we would be appalled, we would be saddened, we would be angered. What we couldn't be was untouched.
"I was mortified," Selig recalls. But he also had to look to the question of what to do next with his sport. The first stop was the owners' meetings, but with the world changed and the airports closed, the agenda there no longer made much difference.
"I went down to the Pfister," Selig says, "and people were just milling around, bewildered. Nobody knew what to do. The Seattle people ended up driving home. They got a car and they literally drove home. Nobody knew what to do."
The immediate question for baseball, after the first burst of chaos and alarm died down, was when to resume its schedule. There was the natural inclination to simply go forward as soon as the travel logistics allowed, because this is what the baseball schedule does; relentlessly, annually, always.
But on the other side of the question, there were the horrific facts of this tragedy: thousands of deaths, America attacked on its own shores. What consequence did balls and strikes and hits and runs and errors have in this terrible context?
Maybe the game should not go on for some time. Maybe, in deference to this crisis, the season should simply be abridged.
Selig agonized over these issues. But in his office, there is a copy of a letter from Franklin Delano Roosevelt sent to then commissioner Kenesaw Mountain Landis, urging baseball to continue playing during World War II. For Selig, this historical reference point from a wartime president served as a guide.
"In our function as a social institution -- and baseball is a social institution -- we wanted to be not only sensitive, but we wanted to play our small role in the recovery process," Selig says. "It was a painful time, an emotional time, but we did fulfill that role."
Sept. 11 had been a Tuesday. Between those who thought that the game should resume by the weekend, and those who thought that resuming it was insulting, Selig chose to have the season resume six days later. The games that were missed were subsequently added to the end of the regular-season schedule.
Perhaps the most lasting memory of that following Monday night, when baseball came back, was the recitation of a poignant poem by the Hall of Fame broadcaster Jack Buck, before the Cardinals played the Brewers in St. Louis.
During his remarks, Buck paused to ask aloud the question that everyone was asking: "Is it right to be here?" The crowd at Busch Stadium answered him with a resounding ovation.
"When Jack Buck asked: 'Is it right to be here?' and the crowd roared, it was a very emotional time," Selig said. "I don't mind telling you that I cried that night."
The season, the pennant races, the home run record chase, all resumed. The postseason was no longer the October Classic, because it finished in November, but it also finished with a spectacular World Series, with the Diamondbacks beating the Yankees in seven games. But there was something to be said, given all that had happened, for having a New York team on hand.
"With the World Series being in New York that year, that was fitting," Selig said. "When the president threw out the first pitch and the crowd chanted: 'USA! USA!' there was not a dry eye in the house. You could not believe it. There was never anything like it."
American society was irretrievably changed by the events of Sept. 11, 2001. But American society carried on. Baseball was part of that.
The game does not cure cancer or lower taxes, but it has been part and parcel of getting through difficult times in America, dating from Union soldiers playing baseball in Civil War encampments.
The game didn't solve any of the world's problems in the autumn of 2001, but for many of us, the resumption of the national pastime made those issues more bearable. The game can symbolize shared good times, but it is not only about the good times.
"I'm really proud of the way our institution carried on during that instance, a terribly difficult period for our entire nation," Selig said.
Baseball, an integral part of American society even in the most difficult of times, shall not forget, should not forget, cannot forget.
Mike Bauman is a national columnist for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.