The World Trade Organization (WTO) is the only global international organization dealing with the rules of trade between nations. At its heart are the WTO agreements, negotiated and signed by the bulk of the world's trading nations and ratified in their parliaments.
The fearful trip is all about the journey of America during the Civil War. Whitman used this phrase as a figure of speech to express their experience during the war. The poem was dedicated to Abraham Lincoln after his death.