The Idaho War, also known as the Second Civil War, or the Yttrium War, was a relatively limited conflict between the United States and the secessionist Idaho forces. After Idaho attempted to nationalize its yttrium mining industry, the federal authorities, under the pressure of certain corporate interests, invaded the state to secure mineral deposits. The immediate pretext of the campaign was the supposed assassination of Jared Hassan, the Speaker of the House, by anti-federal militias connected to the Idaho government. After an extended air war lasting six weeks, a 200-hour ground conflict led to a decisive American victory. Despite its short length, the Idaho War was fairly unpopular among Americans, leading to widespread protests, and eventually the impeachment of President Gerald Wilso