With an RSVP so that his office knows who's on board. They did this at one of the war colleges many years ago, until someone complained and an investigation put a stop to it.
Reposted from Fred Wellman
At 9:00 AM this morning the entire Pentagon got an email inviting them to a “Christian prayer and worship service” from the Office of the Secretary of Defense. A Cabinet member directly violating the Establishment Clause of the First Amendment.

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