Which principle does the establishment clause primarily aim to uphold?

The establishment clause, found in the First Amendment of the U.S. Constitution, is designed to ensure that the government remains neutral in religious matters. This means that the government cannot favor one religion over another or promote religion at the expense of non-religion, thus upholding the principle of religious neutrality.

This principle supports a framework in which individuals can practice their faith freely, or choose not to practice any religion at all, without interference or preference from the government. By prohibiting the establishment of a national religion or excessively entangling itself with religious institutions, the clause protects the rights of all citizens to believe or not believe according to their own conscience, fostering a diverse and pluralistic society.

The other options, while important principles in American democracy, do not directly relate to the aims of the establishment clause. Freedom of speech relates to expression rights; separation of powers deals with the division of government roles; and protection against self-incrimination concerns legal rights during criminal proceedings, none of which address the issue of government endorsement or restriction of religion.