Why did the due process clause need to be added even through it was already in the us constitution

No state shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any state deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.

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the  wilmot proviso  was designed to eliminate  slavery  within the  landacquired as a result of the mexican war (1846-48). fearing the addition of a pro-slave territory, pennsylvania congressman david  wilmot proposedhis amendment to the bill.

living during the great depression had a major affect on the mentality many people. a good portion of people who lived during that time do not trust banks. this is likely the result of the many widespread bank failures in the 30s that caused people to lose their life savings.