On a transcontinental train, a talkative traveler takes the seat next to a professor reading a book. The talkative man interrupts the professor with his continual boasting about how wonderful America is, until the professor asks, "Which America?" To the other man's befuddlement, the professor explains there are many kinds of America and that they are all changing. He mentions the political and historical America, the country as part of the world community, and the American personality, which includes immigrants and the American Indians. This quiets the talkative man, and in the dining room, when an elderly woman says she is proud to be a part of America, he asks, "Lady, which America?"
       In Boston, Mrs. Brian O'Riordan, an elderly Irish American living in a modest house dwarfed among skyscrapers, is disturbed after reading in the newspaper that the 1950 census has been completed, and she realizes that she has not been counted. She takes a bus to see the managing editor of the newspaper, Mr. Callaghan, and complains that she is seventy-four, and that the next census will not be for another ten years. Callaghan takes her name and address, then sends reporter Michael Fisher to pose as a census official and get a human interest story from her, but Mrs. O'Riordan recognizes Fisher from the newsroom and reprimands him. Callaghan now sincerely tries to help, calling a number of census bureau officials, but they refuse to offer assistance. Indignant, he calls connections at Congress and the White House, and drives with Fisher to Mrs. O'Riordon's home with flowers to apologize. A man from the census bureau then arrives, saying his office received a call from Washington. The census taker becomes impatient when Mrs. O'Riordan is long-winded in answering the questions, but Callaghan, enjoying the bureaucrat's discomfort, advises her to answer in her own way, as they have all afternoon.
       African-American military and civilian leaders are shown and lauded; persons shown include Brigadier General Benjamin O'Davis; his son, Lt. Col. Benjamin Davis; Jackie Robinson; Jesse Owens; Joe Louis; Sugar Ray Robinson; Levi Jackson; Lena Horne; the Perry Brothers; Marian Anderson; Ethel Waters; Duke Ellington; Louis Armstrong; Eddie Anderson; Justice Francis Rivers of the City Court of New York; Judge Jane Bowland of the New York Court of Domestic Relations; noted radiologist Dr. Benjamin W. Anthony; Congressman Adam Clayton Powell, Jr.; the Right Reverend Bravid Harris; Irvin Molleson, appointed to the Federal Bench; Pauly Murray, former deputy attorney general of California; architect Paul Williams; the 1946 mother of the year, Mrs. Irma Clement; Dr. Ralph Bunche; and the late George W. Carver. A statue of Booker T. Washington is shown.
       Hungarian-American Stefan Szabo raises a family of six daughters while running a company that produces "Szabo's Best U.S. Hungarian Paprika." On the first day of summer, he complains that he will have no peace until his daughters marry. They respond that only that week he turned down proposals from five suitors for Rosa, the eldest, as he was unhappy with the "Smiths, Cohens and O'Rileys" who pursue her. He reserves his greatest dislike for Greeks, because, he says, Hungarians have hated Greeks for 500 years. As Rosa walks to the bus to go to business college, Icarus Xenophon pulls up his car alongside her, and they fall in love at first sight. He offers her a job and drives her to school, and she tells him that her father is afraid she will fall in love before she marries, which Hungarian girls are not allowed to do. Icarus confesses that he has never been in love before, and by the time they reach school, he proposes. When he shows her his confectionary store, he reveals he is Greek, and she says she cannot marry him because Hungarians, especially her father, hate Greeks. He convinces her, however, to stay and work for him. As she works, they stare at each other, then realize they cannot stand it any longer. When Rosa tells her father the name of her employer, he gets worried, but she quickly says that he has a pretty wife who works in the store. Sam, the youngest daughter, decides to investigate, and at the store, she sees Rosa and Icarus kissing. She tells Papa, and they collect all the family members to descend on the ice cream parlor. Papa accuses Icarus of being untrue to his wife, and Icarus protests his innocence. When patrons of the nearby Graeco-American Athletic Club arrive, they admire Rosa's sisters. Rosa then enters with groceries and shows her father her wedding ring. Everyone congratulates them, and Rosa tells her father, who sits forlornly at the counter, to get used to it. Icarus relates that when his father was upset, he used to make coffee. Papa vows never to drink Greek coffee, but when he is shown that the coffee offered is "Washington Post Coffee," he drinks it and embraces Rosa and Icarus.
       It is stated that the fighting men of the United States are composed of all heritages and creeds. Following his term of duty in the Korean War, Maxie Klein rings the bell of Mrs. Wrenley and introduces himself as a buddy of her deceased son Jack. She is visibly upset when he mentions his Jewish name and says she does not recall Jack ever mentioning a "Maxie," but when she mentions he always wrote about "Jo-Jo," he says that is what Jack called him. He reads Mrs. Wrenley Jack's last letter, in which Jack writes that freedom, democracy and tolerance are not mere words, but are the real reason he is fighting. Mrs. Wrenley cries, as Jack, in the letter, calls Maxie "my kind of people" and his best pal. As Maxie prepares to go, Mrs. Wrenley says she would be glad to rent Jack's room to him, if he was not returning home, and that she'd like to write his mother about what a fine boy she has. Maxie kisses her, then leaves.
       A Texan rolls a cigarette and talks about the "America of wide open spaces," and the "funny ideas" and exaggerations that people have about Texas. With tongue in cheek, he downplays the state's size, the ease of finding oil there, its large ranches, hospitality and pretty girls, and its independence from the rest of the country. He warns with a wink that people should not listen to the rumors about his state.
       In 1944, Adam Burch, a new minister, is ordained to serve at St. Thomas Church in Washington, D.C., where the President of the United States attends when his schedule permits. Rev. Burch, somewhat overwhelmed at the prospect of preaching before the president, decides to prepare a sermon on "spiritual manifestations of our society as reflected in the war effort." The president does not show up, however, and Burch preaches to yawning parishioners. After five weeks of similarly high-minded sermons, Burch asks the sexton his opinion of the sermon he is preparing, and the sexton tells him he is not doing a good job. He points out that Burch has been preaching to one man, rather than to the whole congregation. In the reverend's next sermon, he admits he was in error and that he has learned that he must function as a minister for the entire congregation. Afterwards, a secret service man comes to his office to say that the president came into the church just as he began his sermon and listened from the back. The metallic sound of crutches is heard when the president, as just one of the flock, comes to the door.
       In an elementary school in San Francisco, the teacher, Mrs. Coleman, calls on Joseph Esposito to do a division problem on the board, and when the boy says that the numbers are too small, she suggests he needs glasses. At home, Joey's father, a proud Italian-American immigrant, argues with his wife when Joey brings home a letter suggesting he should go to the optometrist, then goes to see the teacher himself. He complains that glasses will make Joey different from his friends, but she contends that his schoolwork is suffering. Papa refuses to allow the glasses, but when Joey gets a headache from reading, his mother takes him to the optometrist. While playing with friends, Joey sees his father coming. He takes off his new glasses just as he is about to jump for a ladder and missing it, falls into a pile of bricks. As Joey recovers from his injury, Miss Coleman tutors him, and when she arrives for supper one night, Papa puts on glasses himself. Everyone looks surprised, then Joey puts his own on, and Papa tells him they look good. A narrator relates that ours is a big, wonderful country, proud of its past, strong in its present and confident in its future. It is one nation: the land of the free and home of the brave.