Unalienable rights and individual free agency guarantee the rights of minorities and of individuals.
Unalieanable rights are rights that cannot be taken away, not even by a 100% majority vote. Unalienable rights cannot be legislated away, and they cannot be ruled away by a supreme court. They cannot be contracted away. Governments and institutions cannot add qualifiers to unalienable rights, and they cannot dilute them. They have no authority over unalienable rights.
America is a country of unalienable rights. The Constitution does not grant those rights. The Constitution explicitly tells the government that it cannot, and shall not, infringe on those rights.