A man gets up early to claim a good spot on a Boston street corner. He wants to watch a parade: the President's marshal, government cannon, federal infantry and dragoons, and he hopes the fifes will play "Yankee Doodle." Nothing in the poem says why the troops are there. The date in the title and the sight of federal soldiers marching through Boston are usually linked to 1854, when the city saw a fugitive slave returned to bondage under federal law. Whitman never names slavery, though, and that silence is part of the method. The poem works as satire even for a reader who knows none of this, because its target is a city that cheers its own surrender.
The trick is the speaker's voice. He is a cheerful, gullible spectator who "love[s] to look on the stars and stripes" and admires how "bright shine the cutlasses." Yet the details he reports are chilling: "Every man holds his revolver, marching stiff through Boston town." The repeated "Way for the President's marshal! Way for the government cannon!" sounds like a herald's cry, and the pomp becomes oppressive. Calling the crowd "Jonathan," a nickname for the typical New Englander, turns the whole city into one easily flattered bystander.
Then the parade gets company. A fog rolls in, and out of it limp ghosts: "Cock'd hats of mothy mould! crutches made of mist!" The sounds are as vivid as the pictures. The soft, mouthy "m" in "mothy mould" and "made of mist" makes the phantoms seem to dissolve as you say them. Their wooden legs, slings and bandages suggest old soldiers, and the phrase "Yankee phantoms" points to Boston's own past, though the poem never says which war. They weep and groan, and the speaker scolds them: "For shame, old maniacs!" His reasons are damning. They are spoiling the show, and the living are so "well dress'd" and "orderly." The line "Is this hour with the living too dead for you?" flips the poem's logic. The ghosts are the ones with feeling, and the living citizens are the dead.
The second half swerves into black comedy. If Boston has abandoned its revolutionary spirit, the speaker says, it might as well complete the job by sending a committee to England to dig up King George's coffin and ship the bones home on a "black-bellied clipper." The verbs march along briskly: "unwrap him quick," "box up his bones," "glue those that will not stay," and finally the twice-repeated "Clap the skull on top of the ribs, and clap a crown on top of the skull." The word "clap" is cheerful and workmanlike, and it makes monarchy look like a shabby craft project, a dead king assembled as a "centre-piece." The speaker's closing sneer, "The crown is come to its own, and more than its own," says the king has won without a battle.
None of this is held together by rhyme. The poem is free verse, and despite the title it has no ballad stanzas or refrain. What it keeps from the ballad is the public, storytelling voice of a street song. Lines stretch long and loose like a marching column, then snap short on commands: "Retreat then! Pell-mell!" Exclamations, imperatives and questions keep the poem noisy and theatrical, so we hear a crowd as well as a speaker. Some long lines spill onto an indented second line, as though the poem cannot fit its own parade on the page.
The last lines drop the pretence and turn on the crowd: "You are mighty cute—and here is one of your bargains." "Bargains" suggests a deal in which something precious was swapped for peace or convenience, and the poem leaves us to decide what. Its force comes from never lecturing. Whitman lets us listen to complacency talk itself into disgrace, and then the ghosts' tears seem the only sane response in the street.