What was one success during the reconstruction era?

Explanation:  hold the nation together

Reconstruction, in U.S. history, is the period (1865–77) that followed the American Civil War and during which attempts were made to redress the inequities of slavery and its political, social, and economic legacy and to solve the problems arising from the readmission to the Union of the 11 states that had seceded at or before the outbreak of war. .

Many African Americans participated in new state and local governments, which worked for equal rights.  Holding the nation together  was a success

answer; andrew jackson approved nullification by signing it into law,and john calhoun opposed it saying it was unconstitutional;

c. troops marched forward in close formation against newer, more accurate weapons