In this famous ensemble number from the movie West Side Story, the women are basically arguing with the men about the virtues of living in New York City instead of their native Puerto Rico. Anita and the other women are in favor of "America" while the men presumably wish to return to San Juan.

The supposedly ideal life in Manhattan is extolled by the women, who mention the obvious prosperity (such as skyscrapers and Cadillacs), the ability to buy on credit, and the general sense of freedom, which they contrast with what they describe as the poverty of Puerto Rico. Bernardo and the men answer that the problem with "America" is mainly that they, as Latinx immigrants, are discriminated against. Anita sings that:

Buying on credit is so nice!

to which Bernardo answers:

One look at us and they charge twice.

The song seems to show the female members of the ensemble looking at the mainland US in idealistic terms, and celebrate its material wealth and the possibility that all people, regardless of their backgrounds, will share in it. The men, on the other hand, cynically dismiss these notions and point out that, in leaving Puerto Rico, they have come to a place that is a hotbed of bigotry, grime, organized crime, and other unsavory things. So the song in the movie is presented with the women taking sides against the men.

In the Broadway version, on the other hand, the two women Anita and Rosalia are instead arguing with each other about the benefits of New York or San Juan (respectively). Regardless of the version, the core issue is: does the good in "America " outweigh the bad, and is "America" really a land for everyone, or is it still at this point (the late 1950s and early 1960s) a place that rejects minorities and anyone not of the dominant group?

The irony is that Puerto Rico is actually part of America and of the US specifically (something that is pointed out in the Broadway version of the song). So it is "America" as a cultural concept (which is why I place it in quotes) that the song references. This is the subtext intended to be invoked by Bernstein and Sondheim which perhaps most audiences of that time weren't yet prepared fully to appreciate.