Whitman's simple, optimistic poem is amazingly among those which caused uproar in his day.
Whitman's poem celebrates the great level of American civilization in its [America's] ability to deliver a parcel across "a thousand miles" through storm and snow in a mere 3 days. But citizens suffering misfortune at the time, due to the March blizzard of 1888 that blindsided the coast, took great offense at Whitman's optimism and good fortune and many wrote poems mocking Whitman [though most of these took particular aim at "The First Dandelion," published 6 days earlier].
For more, see these notes from the Walt Whitman Archive: http://www.whitmanarchive.org/published/periodical/poems/per.00126
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