As Adrienne Rich alludes to the movie Citizen Kane, it's important to concentrate on that for clues to the meaning of her poem, "Amnesia."
Citizen Kane revolves around the hidden meaning of the word "Rosebud," spoken by Kane when the movie opens, which is actually showing the audience the end. The rest of the movie is a search (in flashback) to uncover the man Kane really was, what "Rosebud" was, and what it meant to Kane. The "newsreel reporter" never finds the answer, but the audience does. It is printed on Kane's childhood sled, which he had when his mother sent him away to live with Thatcher (her banker) to live. It would seem, after seeing the snow globe in Kane's hand as he dies— whispering "Rosebud"—that the true person of Kane is the lost boy sent away by his mother, living with a stranger, and—as the movie shows—ultimately losing his idealism as he serves the masters of power and money.
So loss of innocence is a central theme in the movie, both in terms of how the child is forced to deal with the devastating separation from his mother, as well as the loss of his dreams of helping those who cannot help themselves: his loss of idealism.
In Adrienne Rich's poem, the "earliest American dream" seems attached to the mother (in "Kane") sending her son away to realize a better life than she has had. This dream doesn't seem as much a concern as the separation does. The "black-and-white" indicates something old, such as the movie—and many others like it, produced especially in the 1930s and 1940s. Rich may referring to the way things seemed in those days—based on her age, things she may well have seen growing up (she was born in 1929). Rich may be describing how "in the old days," things seemed better somehow: the snowflakes in the movie are "incandescent:" glowing or bright…symbolic of youth?
However, there is also a contradiction: perhaps based on the promise of those days—the American dream— and the reality, maybe something Rich experienced herself: "adding up to the cold blur of the past." If it were only a blur, we might think the past flew by. However, "cold" gives the reader to believe that whether they flew or not, the memories are not pleasant or warm.
Rich presents a transition with "But first…" For here we stop recalling the movie's allusions and come face-to-face with "the putting-away of a childish thing." This alludes to the Bible's I Corinthians 13:11, that says:
When I was a child, I talked like a child, I thought like a child, I reasoned like a child. When I became a man, I put childish ways behind me. (NIV)
The author's concern is not in the "putting away," but in the leaving:
Becoming a man means leaving
someone, or something—
The poem's closing reveals a perspective that may allude again to the snow globe in Citizen Kane. The camera offers the audience a perspective of Kane's last glance—through the snow—of his childhood home, represented by the house in the globe.
Rich refers to being that which is left behind, looking from the other direction through the snow, and the feeling of isolation and loneliness that she (or the speaker) has suffered in watching "him" leave.
The poem's title is "Amnesia"—forgetting. Rich starts out the poem by stating:
I almost trust myself to know...
She hasn't quite forgotten.
The American dream was extremely important, but perhaps Rich is drawing the reader's attention to not what one moves toward to obtain a dream, but what the dreamer leaves behind.