You can also argue that suburbanization goes back even further. In fact, Delores Hayden does that in
Building Suburbia. In the mid-19th century, cities expanded their limits so far that it took decades to fill up the space. Buffalo, NY is a case in point. In 1854, the city expanded to take in the village of Black Rock along the Niagara River as well as land to the north, east, and south that make up the present city, but was nothing but cow pastures and farm fields at the time. Much of it remained that way until after 1900. (See
1894 Buffalo City Atlas.
The area north of the Pan American Exhibition grounds was finally developed in the early 20th century, from the 1910s to 1930. It was Buffalo's "suburbia" then. My immigrant grandparents escaped the crowded conditions in Polonia (the Polish part of Buffalo's East Side) to move to newer, nicer housing in the Grant-Amherst area.
That wasn't a pattern unique to Buffalo, either. The neighborhood I live in here in Jamestown is near the city line and is a mixture of 1920s and post-WW II homes. Further south, most of the homes are vintage 1960. In the southeast corner of Jamestown, there's suburban style developments from the 1960s and 1970s. There are numerous suburban-like neighborhoods within the city limits of Albany, Troy, and Schnectady, too. In fact, when I lived in the Albany area in the 1990s, there was still significant land available for development in both Troy and Rensselaer, and builders were putting up houses on that land.
Too many people assume that because the widespread development of towns outside the city limits didn't occur until after WW II that suburbanization started then. The fact is that was about when many cities, especially in the Northeast and Midwest finally filled up the land within their city limits (and they were prohibited by law from annexing neighboring areas). What too many people today don't realize is that people's needs and wants changed over time. Moving from a crowded tenement or from a tiny little shotgun shack housing two or three families to a newer home with a basement and spacious apartments on each floor and a yard big enough for a garage and a little garden was the 1920s version of the 1950s single family cape on its quarter acre lot or the 1970s rancher with its bath and a half, attached garage, and half acre estate. The beautiful Victorians and Tudors that dot city neighborhoods today were their eras' versions of the 2000's exurban McMansions.
We're Americans, the descendents of people who mostly came here to get land of their own, even if they actually never did accomplish it. Owning the land we live on (even if it's only an apartment) will probably remain important to most Americans for the foreseeable future, even if it's only a dream. It's just something that's ingrained in us in a way that doesn't happen in most places in the world. Maybe it's in the water.