Questions: According to the Gettysburg Address in 1863, the Union fought in the Civil War primarily to defend government by the people and for the people.

The answer is defend government by the people and for the people.

This option aligns with the core message of the Gettysburg Address. Delivered by President Abraham Lincoln during the American Civil War, the address emphasized the principles of democracy and the importance of preserving a government that is of the people, by the people, and for the people. Lincoln's speech underscored the Union's commitment to these democratic ideals as a justification for the war effort.

The Gettysburg Address does not focus on religious themes or the promotion of Christianity. While religion played a role in the lives of many individuals during the Civil War, it was not the primary reason cited by Lincoln for the Union's involvement in the conflict.

The address does not mention capitalism as a primary reason for the war. While economic factors were certainly part of the broader context of the Civil War, Lincoln's speech focused on the preservation of the Union and democratic governance.

The concept of states' rights was more closely associated with the Confederacy's justification for secession. The Union, as represented by Lincoln, was more focused on preserving the nation as a whole rather than emphasizing states' rights.

The Gettysburg Address did not call for rewriting the Constitution. Instead, it reaffirmed the principles of the Declaration of Independence and the Constitution, emphasizing the need to preserve the Union and its democratic foundations.