Why was will Clark proud of what he accomplished

I assume that by Will Clark you are referring to William Clark, the explorer, and not Will Clark, the former San Francisco Giant's first baseman. William Clark the explorer would have been proud of what he accomplished because he, along with Meriwether Lewis, led the American expedition across the recently acquired Louisiana Purchase in the early 1800s. Upon completing their journey, Lewis and Clark were the first in recorded history to traverse the North American continent from ocean to ocean.