Militarily, Nebraska played a minimal role in every confrontation between the United States and the Confederate States. Although it contributed many of its native sons to the USA's efforts, the state itself was never a front.
Nebraska was badly hit when the Yellowstone Supervolcano erupted. It was down-wind of the eruption and so covered with ash. No one was sure how many feet, but the U.S. wouldn't have the fleet of bulldozers and trucks to remove it.