For example, I was on a high school football field with over 100 other people, just waiting for it to be dark enough to watch things explode, when the national anthem began to play. Everyone stood up and turned to face the flag. There were people of every background, age, and race class around me and for that one minute (or however long it takes someone to sing the national anthem) we were all just celebrating America.
Is there anything more American?
In writing, there are hundreds of things people will tell you to do in order to connect to your readers, but I'd say universal experiences are probably one of the best things. And I'm not saying that you have to have a scene where the hero hears the anthem of his or her state/country/villiage/etc. and get's overly emotional and goes on a vengeance mission to help his fellow man (or dwarf/elf/vampire/etc.)
For example, in the popular series (and current personal obsession) The Hunger Games, there is a scene, I believe in the second book Catching Fire, where the MC, Katniss, witnesses a crowd of people who whistle a meaningful tune. The crowd is clearly united and in support of the MC. The author doesn't need to spell out the feeling that the MC gets, or even the expression on the faces of the crowd. My mind immediately connected with the experience, even though I don't live in an oppressed district and I don't know anyone who has ever been killed in the name of entertainment. I still got it.
It would be the same if a writer described watching fireworks with a friend. You can't put on paper the unequaled amazement of a child watching the colorful explosions high above her head, or the beauty of the golden strands that trail down to earth after the initial color has faded from the sky. But writing a brief description like that would bring any reader (who has been fortunate enough to see fireworks) back to a time when they enjoyed the simple entertainment of a fireworks display, whether they were a child or an adult.
It's the little scenes that help connect the reader to the characters in a story. Think of your favorite book, I'll bet there's at least one moment that you identified with the MC or a supporting character, whether you realized it while reading or not.