The middle class is a fabrication. It's an income bracket created by capitalism, not a true analysis of one's association to the means of production and labor. It's "real" in the sense that many people identify themselves to it, but it's not real in a Marxist sense.
A vast majority of people in the middle class are the proletariat. Some of the people in the middle class are petite bourgeois.
Edit: I think your question is a good one, simply because so many people do see themselves as part of this Middle Class first before they think of themselves as workers or business owners, but I think that's a sign of effective capitalist propaganda meant to distract the workers from their relationship to labor. The Middle Class largely is made up of people who need to be reeducated to understand that they are part of the proletariat and the bourgeois have been robbing them for centuries.
America is interested in Venezuela because of their rich lithium deposits, the rest is just noise to generate casus belli