Can Amish join military?

The Amish - and other Anabaptist sects - are centered around an ideology of anti-militarism. However, they don't actually join the church until they're adults, and do so by their own volition. An Amish person could join the military prior to actually joining the church and theoretically not face repercussions for having done so during the time of their "wild spring". The US military has no policy prohibiting the Amish from joining.