Why does franklin believe that any constitution the convention approves will be an imperfect document

Because humans are not perfect and have their own prejudices and bias so no document will ever be "perfect".

congress failed to remove johnson. but it did succeed in getting control of efforts to re-build the south following america's civil war. radical republicans wanted to punish the south for starting the war. they also wanted to be sure new governments in the southern states would support the republican party.

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