Service members should not be required to say "So help me God" in their enlistment and reenlistments. This statement may conflict with their spiritual beliefs or non-beliefs, and indicates that the oath to serve their country is synonymous with an oath to a higher being (assumedly your Christian god). It also contradicts Article VI of the Constitution, which prohibits requiring religious tests to hold an office or public trust. Congress should amend Title 10 § 502 so this is no longer a requirement in the oath. Members should have the choice to either say this portion of the oath, or omit it, based on their beliefs.
This goes against the First Amendment of the US Constitution which prohibits the making of any law that impedes the free exercise of religion.