I agree, Gregg......and there is a HUGE difference between that high school student thanking his/her god for helping them through those years, just as they would thank parents, teachers, etc., and say, an elected official coming to that graduation in a public school and saying something like, "only with the help of Jesus Christ (or "only by the goodness of Allah", or "only with the intervention of the divine Goddess", etc), have these students been able to get through their school years, and unless they continue to follow (name of god here), they will not meet with success in life."
One is a heartfelt admission from an individual person of their belief, and inappropriate for a government official. It doesn't seem all that hard to me. Government officials, as their own private person, can hold whatever beliefs they like, and govern their lives according to that belief, but in their official capacity as a government official can simply not elevate one religion over all others or over no religion at all, because this country is not a theological country, it is a pluralistic secular country with freedom of religion for all people, and freedom FROM religion for all people as well, in any official government capacity.