The alliterative moments in "Facing It" help the speaker intensify the sound of the language, often giving it a rhythmic and passionate quality. In line 1, for example, the quick succession of the gentle /f/ sounds in "My black face fades" makes this opening line sound pleasing but also assertive and urgent, thereby hinting at the intensity of the speaker's emotional state.
Later, in lines 11-13, the /v/, /m/, and /d/ sounds all alliterate:
the Vietnam Veterans Memorial
again, depending on the light
to make a difference.
Most notably, the strong /v/ sound places emphasis on two of the poem's most important words, which ultimately clarify the surrounding context: "Vietnam Veterans." The /m/ and /d/ sounds, on the other hand, simply enhance the musicality of this section, making it sound muscular and contoured by infusing the lines with blunt, rhythmic sounds.
For another example, look to lines 18-21:
Names shimmer on a woman's blouse
but when she walks away
the names stay on the wall.
The /w/ sound defines these lines, appearing multiple times and generally lending the section a vaguely wobbly sound that aligns with the speaker's feeling that the names are gently moving back and forth. The alliterative /sh/ sound in words like "shimmer" and "she" add to this sense of shuffling and swaying.
There are, of course, a number of other moments of alliteration throughout "Facing It," most of which work in ways that are similar to the ways outlined above. On the whole, the speaker uses alliteration to both carve out important words and enrich the poetic sound of the language, essentially creating a textured and cohesive effect that is satisfying and melodic.