I think that the statement is accurate in describing Whitman's poem. To a great extent, all elegies are works that strive to mourn the loss of an individual through death but also affirm the life that they led. The elegy's birth only comes out of an affirmational rationale to honor the dead. This poem is no exception. Whitman writes it to mourn the loss of Lincoln, but honor him at the same time. "The great star" is a line that directly refers to Lincoln. The fact that it shone becomes the reason that the poem is written, but also because that source of light and beacon "early droop'd" is another reason why the poet feels the need to compose the poem. Even the mere title plays with this juxtaposition. On one hand, the idea of blooming lilacs affirms life itself. Recalling when they last did so brings the notion that such beauty and purity are no longer present. To honor such a condition is to pay homage that it has now passed, and the poem appropriates this same demeanor towards Lincoln.