How did the civil show the flaws of the us Constitution?

The most obvious constitutional result of the Civil War was the adoption of three landmark constitutional amendments. The 13th ended slavery forever in the United States, while the 14th made all persons born in the United States (including the former slaves) citizens of the nation and prohibited the states from denying anyone the privileges and immunities of American citizenship, due process or law, or equal protection of the law. Finally, the 15th Amendment, ratified in 1870, prohibited the states from denying the franchise to anyone based on "race, color, or previous condition of servitude."