Until recently, Section 3 of the 14th Amendment was an obscure part of the U.S. Constitution.
The amendment is better known for its first section, which guaranteed individual rights and equality following the abolition of slavery. Section 3 of the 14th Amendment was created to tackle a different problem related to the Civil War: insurrection.
It prohibits current or former military officers, along with many current and former federal and state public officials, from serving in a variety of government offices if they “shall have engaged in insurrection or rebellion” against the United States Constitution.
This section was created after the Civil War as part of the 14th Amendment to bar military officers and civil officials who joined the Confederacy from serving in government again.