What defense mechanism is identified when a client cannot recall traumatic abuse from their childhood?

Repression is identified as a defense mechanism where a person unconsciously blocks out memories, thoughts, or feelings that are too painful or threatening to acknowledge. In the context of the question, when a client cannot recall traumatic abuse from their childhood, this is a classic example of repression at work. The individual is not consciously aware of these memories, as the mind has pushed them into the unconscious to protect the person from the distress associated with those memories. This protective mechanism can prevent the overwhelming feelings of anxiety or sadness that could arise from recalling such traumatic events.

Projection involves attributing one's own unacceptable thoughts or feelings onto someone else, which does not apply in this instance. Suppression is a conscious effort to push away negative thoughts, while repression is unconscious. Rationalization involves justifying behaviors or feelings in a logical manner, which does not correlate with the inability to recall traumatic events. Thus, the description of the client's experience aligns perfectly with the concept of repression, verifying that it is the most accurate answer.