Is there a dish in the world that exhibits American comfort food more than spaghetti with meatballs?
I hear you man. It's probably my favorite. The spaghetti, tomato sauce and meatballs are amazing to have any day of the week!
Darn straight!  And there's a reason I said "American."  Though it may be inspired by Italian dishes, it was Italian-American immigrants that came up with the dish.
Italian because, in Italy, meatballs are smaller and only served with egg-based baked pasta.
However, various kinds of pasta with meat are part of the culinary tradition of the Abruzzo, Apulia, Sicily, and other parts of southern Italy. A recipe for rigatoni with meatballs is in "Il cucchiaio d'argento" ("The Silver Spoon"), a comprehensive Italian cookbook known as the "bible" of Italian cooking. 
In fact, in Abruzzo, chitarra alla teramana, is a long spaghetti-
Spaghetti with meatballs
Spaghetti and meatballs or spaghetti with meatballs is an Italian-American dish consisting of spaghetti, tomato sauce and meatballs.
History.
It is widely believed that spaghetti and meatballs was an innovation of early 20th-century Italian immigrants in New York City. The National Pasta Association (originally named the National Macaroni Manufacturers Association) is said to be the first organization to publish a recipe for it, in the 1920s.
Italian writers and chefs often mock the dish as pseudo-Italian or non-