For this Dharma talk I would like to share some impressions that I have learned while being Buddhist as an enlisted Marine and as a Naval officer, and offer some advice on working with non-Buddhists and also with other Buddhists who may not understand your reasonings for being in the armed forces. I understand that everyone may have had different experiences so please do not take this as "scripture" but following Buddha's advice to the Kalamas, if you can put this into practice for yourselves and make it work, then do so!
In my experience, I think most Buddhists simply are quiet about their religion, and this is understandable. The reality is that we are a minority faith in an overwhelmingly Christian environment. For some, being a Buddhist is an extension of family and cultural traditions, while for others it may be a new and exciting spiritual path. I have experienced a little of both, coming from a Korean Buddhist family background (but never practiced at home) and "converting" to Jodo Shinshu Buddhism, a Japanese Buddhist tradition, and learning its rituals and teachings.
Most Buddhists, including "converts" do not necessarily "shout out" their faith, it is simply part of the personal identity, expressed mostly at home with family or with other Buddhists. There is certainly nothing wrong or unusual about this; many people of other religions behave similarly.
However we may encounter others who discover our Buddhist identity, because we leave Buddhist books out in our barracks room, chant audibly, or otherwise express our Buddhist faith openly. Thus we become obligated to "defend" our Buddhist identity, and I use that word on purpose, because we are interacting with people who may know very little about Buddhism, or have many misconceptions of Buddhism, and may be curious or hostile. Either way, we end up answering questions, and offering information about Buddha-dharma. This is some of what I would recommend in these situations:
1) Explain Buddhism simply - Many people, when inquiring about Buddhism, really are curious about Buddhism and want to know what you believe. They may know only a little already, or have no idea. Don't try to overwhelm them or impress them with your spiritual knowledge. Words like "Namo Amida Butsu" have great import for Shinshu Buddhists, but means nothing to those who have never heard of Pure Land Buddhism (or don't know Japanese). The Buddha always tailored his Dharma messages to the level of his audience - do the same.
2) Refrain from becoming angry or upset - It may be difficult not to get exasperated when people assume (for the millionth time for me I think!) that the entirety of Buddhist practice is "going OM", or rubbing the fat Buddha belly! Or assuming that Buddhists would make bad soldiers ("wouldn't you all just run away?") Take this as your opporuntity to squash the stereotypes and reveal that Buddhists are human beings too! And that it does not get in the way of our jobs; emphasize your professionalism. Remember, you may be the first and only Buddhist that person has encountered. What impression do you want to give? It is like wearing your dress uniform out in public!
3) Find similar grounds - Some need assurance that Buddhism does have a system of morality, and that we do not believe in raping and pillaging at will! All religions and spiritualities believe in some version of the Golden Rule "Do unto others as you would have had done unto yourselves." Find common ground for spirituality.
4) Use chain of command - At some point in our careers we will encounter people who actually do feel frightened and threatened by Buddhism. If you are dealing with a nightmare of a senior leadership, whom you believe is harassing you because of your religious identity (and I worked for a SSGT who believed that all Marines should be forced to be Christians!), always use your chain of command. Also go to your chaplain. They are there to help all servicemembers, not just for people of their own religion. You have a right not to be hassled and prevented from doing your work because of your religion. It is very sad, but there is probably very little you can do to change these peoples' fears (although it does happen); sometimes the best thing you can do is to avoid them; if you can't then look for assistance.
5) Be familiar with religious accommodation - For those of us in the Sea Services, there are guidelines providing for free exercise of religion. Two of these are OPNAVINST 17301.D "Religious Ministry in the Navy" and SECNAVINST 1730.8A "Accomodation of Religious Practices" which provide for free exercise of religion for all naval service members. There are similar instructions for Army and Air Force.
Above all, don't feel that you have to be defensive or "hide" your Buddhist faith unnecessarily. If you don't want to "broadcast" your beliefs, that is fine, if you want to practice openly or become a lay leader for your command, that is also commendable.If you are new to the military and a Buddhist know that there is someone who has gone before you and experienced it! Share your experiences!
Namo amida butsu