When faced with essay questions of this sort, your answer should almost always be something like “to some extent.” This is because these questions are typically meant to encourage you to see both sides of the issue.
On the one hand, you can say that the changes over this time period were truly revolutionary. The most obvious example of this is the fact that slavery ended. That is a very revolutionary change because it destroyed an entire economic and social system in addition to changing the Constitution. You can also say that there was a constitutional revolution because the doctrine of states’ rights was essentially discredited and abandoned.
On the other hand, there were ways in which this was not truly revolutionary. By 1877, Reconstruction was over. There was no longer any real effort to bring about true social and legal equality between African Americans and white people. In this way, the changes of this era did not constitute a social revolution. The people who had been in power in the South remained in power and the people who had been poor (slaves and poor whites) remained poor.
The constitutional and social changes between 1860 and 1877 in America amounted to a revolution in the sense that it changed the political status quo that had prevailed since the inception of the country.
During this period, the Civil War (1861-1865) was mainly fought over states' rights, and the issue of states' rights was directly related to the question of slavery. Prior to 1860, the Ninth and Tenth Amendments protected the autonomy of each state in the Union. However, changing Northern views about slavery soon threatened the integrity of American unity. Many Northerners were abolitionists who participated in efforts to undermine the slavery-based Southern economy. They questioned the unwavering commitment to states rights under a system that was stacked against African-Americans. It is telling that both the North and South harbored different views about the war.
Many in the North termed the Civil War The War Of Southern Rebellion or The War To Preserve The Union. Meanwhile, many Southerners called the conflict The War Between The States or The War of Northern Aggression. Neither the North nor the South could peaceably reconcile politically divergent views about slavery. This led to the Civil War, a conflict that was nothing short of revolutionary within American borders. The Civil War directly and unequivocally challenged the idea of state autonomy, an idea that had never before been challenged on such an astounding scale.
Historians maintain that, between April 1861 and April 1865, the North mustered 1.5 million soldiers for the conflict, while the South gathered almost 1.2 million soldiers into Confederate service. Almost 600,000 soldiers died in the war. The conflict also saw many firsts in the history of the United States. The war heralded the advent of America's first income tax. In 1862, Abraham Lincoln signed a bill that imposed a 3% tax on those earning between $600 and $10,000 and a 5% tax for those earning more than $10,000. The bill was amended in 1864 to levy even higher taxes on the people but was declared to be unconstitutional in 1872.
The Civil War also saw the first extensive use of African-American soldiers in the history of the young nation. Additionally, the period after the Civil War ushered in social and constitutional developments that entirely changed the political and economic landscape of the country. Reconstruction introduced three amendments to the Constitution: the 13th, 14th, and 15th Amendments. The 13th Amendment abolished slavery, the 14th Amendment granted full citizenship rights to everyone born on American soil (this included former slaves), and the 15th Amendment granted all African-American men the right to vote. Southern states had to ratify the amendments before they could be readmitted into the Union.
Across the South, newly freed slaves could not only vote, they could hold political office as well. Some became judges, public officials, and even police chiefs. They held positions that formerly belonged to Southern plantation owners and white Americans. These social developments were revolutionary in the sense that the entire Southern political and economic landscape was dramatically and permanently altered as a result of the Civil War and Reconstruction.