That's a rhetorical question, of course. Americans have been drinking wine since well before there was an America to drink wine in.
It's equally true that wine appreciation in America is not a new phenomenon, although it seems to have grown significantly in the last few decades, especially among the middle class. It's definitely true that Americans now spend more on wine. And according to the Wine Market Council, the US wine market has continued to grow in spite of the economic downturn that began in 2008.
However, "American wine drinkers [still] consume much less wine than many other countries on a per capita basis," according to this recently published report by the Wine Market Council. Will millennials (roughly defined as the generation of people born in the early 1980s or later, also known as Gen Y) make the US a nation of wine consumers on par with Italy or France? Here's what the Wine Market Council concludes:
Recent consumption gains for table wine have been driven by many factors over the last few years including the adoption of wine in early adulthood by the large millennial generation, the availability of quality wine at all price levels, and the acceptance of moderate wine consumption as compatible with a healthy lifestyle.
To be fair, wine appreciation in America has waxed and waned over the decades. The current growth cycle in wine consumption in this country began in 1994. With a growing appreciation of wine by coming-of-age millenials, that cycle may continue well into the future.
Postscript. Steve Heimhoff posted a blog titled Can expensive California wines sell themselves to a new generation of wine lovers?, which questions whether Millennials will continue to support the same successful, high-end wineries that earlier generations have. What must pricey wineries do to find a market with that audience? Some, like Pahlmeyer, are betting on social media.