Answer:
Historians and scholars argue that the most important change made by the Reconstruction state governments was the ratification of three constitutional amendments (13th, 14th, and 15th) that abolished slavery, granted citizenship and equal protection under the law to African Americans, and ensured black men's right to vote. These amendments represented a significant shift away from the pre-war social and economic order and expanded the scope of civil rights and liberties for all Americans. Additionally, Reconstruction governments played a crucial role in establishing public schools, building infrastructure, and promoting land reform policies that benefited poor whites and freedmen in the South.