The title of "Siren Song" clues readers into what this poem will be about: the sirens of Greek mythology were half-bird, half-woman creates who lived on an island and would bewitch passing sailors with their voices.
The poem draws from such mythology by describing a beautiful, "irresistible" song that makes men "leap" from their ships to the dangerous waters below. These men are desperate, rushing forward "in squadrons," or groups, despite seeing "the beached skulls" of other men lining the shore of the sirens' island. This journey is clearly a deadly one, but the men can't help it, so enticed are they by this song.
The poem is written in free verse, meaning it doesn't follow any set patterns of meter or rhyme. It does have some structure, however, made clear in these opening six lines: the poem consists of tercets, or three-line stanzas. In a way, this gives the poem a sense of orderly progression, suggesting that the siren is in control of this narrative.
The frequent enjambment of these lines also subtly evokes the siren's allure: as phrases rush past line breaks without pause, readers are continually pulled forward, forced down the page just as those "men" are forced overboard. Take lines 1-3 as an example:
This is the one song everyone
would like to learn: the song
that is irresistible:
The diacope and anaphora of "song," meanwhile, lends a pulsing, hypnotic rhythm to the verse that further mirrors the enchanting pull of the sirens' singing, which apparently makes men lose all good sense:
This is the one song everyone
would like to learn: the song
that is irresistible:
the song that forces men
The mythical sirens have traditionally sirens have been portrayed as frightening, villainous creatures. Yet they also speak to a very gendered anxiety: the story of the sirens revolves around women making men lose their sense of control and behave irrationally. In other words, a woman's allure is held responsible for a man's downfall. Sirens are like the original femme fatales: women who entrap men with their charms.
To that end, note the word "forces" here: the poem is drawing on the idea that the sirens are the ones with all the control in this situation, though by the poem's end readers may wonder if that's truly the case.