What role did Amanda, Tom, and Laura play in the "The Glass Menagerie"?
Apart from the character profiles given above (and good ones, too!), Tom is the pivotal character in the story, not Laura. He is the person in primary conflict, and the story line revolves around his choices and their eventual consequences. Both Amanda and Laura, as endearing as they may be, are flat characters and catalysts, bringing out both the best and the worst in Tom. They create a situational context for the conflict in Tom to work itself out (though not altogether resolved).
In a parallel way, Jim does the same thing for Laura in "the serious conversation" scene when the unicorn is broken. Spectators get the feeling Laura has changed, has taken an initial step forward, even if the outcome of this change isn't clearly seen in the rest of the play.
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