Although this seems to be a favorite question we get asked, I will say right up front that this issue in no way, shape, or form dominates my work as a military chaplain. Very few people I have worked with, (I'm aware of zero) care at all how I end my prayers. That being said...
There is no civilian equivalent to military chaplaincy. So I don't expect people to grasp our complex ministry environment. But every time someone asks me, "Are you allowed to pray in Jesus' name?" I do my best not to show my mild annoyance. I find this question a tad bit short-sighted. If you have never seen a chaplain in uniform, we wear our affiliated religious symbol above our name tape and on our head gear. I am honored (and required) to display the symbol of my risen Lord and Savior every day. Therefore, the common perception that somehow I am restricted in proclaiming my faith is way out in left field.
There are several settings in which I might find myself publicly praying. For example: 1) Chapel. Absolutely no difference in how you might expect a minister or anyone else to pray in church. 2) Chaplain-led spiritual fitness events. Again, it's my event that I have invited Soldiers or leaders to attend, so I feel quite free to pray as I please. 3) Mandatory ceremonies/formal events. During one of these, such as a change of command ceremony, the chaplain is often included in the script for an opening prayer. Since this is a unit event, these prayers are short and scripted. Soldiers are required to attend. Given the pluralistic nature of the military, I am mindful that in the audience there are fellow Christians but also many other religious affiliations in the mix, (as well as those with no faith). I normally choose to end my prayer with something like, "In your strong name I pray," or "In your Holy name I pray, amen." When I walk away from the podium I still have a cross on my uniform, and everyone knows Who I stand for. A mandatory event for Soldiers is just not the place to preach-pray or use the opportunity to make things religiously awkward. Doing so may jeopardize future opportunities.
I will point out here that I have never had a commander tell me not to pray in Christ's name, although I have heard that has happened on rare occasions. More commonly, it's some (not all) chaplains who take issue with this. This is because, more than anyone else, chaplains are schooled in the pluralistic nature of our ministry context and seem to be more sensitive to the issue. Some insist on their free speech to pray in any manner they choose. I cannot say they are wrong. However, most recognize that our environment is a complex one and a one-size-fits-all prayer approach is too simplistic. We have variables to consider that do not exist in civilian ministry. Therefore, I do not expect civilian ministers or fellow Christians to agree or fully understand.
Despite common misconceptions from those looking in from the outside, I have never felt restricted in any way from living or displaying my faith as a chaplain. Quite the contrary, the chaplaincy opens limitless opportunities to extend a voice for matters of faith. The government does not employ us to be missionaries to Soldiers. We are charged with protecting the free exercise of religion (found in the #firstamenedment) including but not limited to our own. It is a privilege that I pray we never lose. So I do not get too wrapped around the axle on how a prayer should end. And I hope you will not judge our work based on this minor issue.