It is NEVER REQUIRED that you sign a power of attorney, but it is a legal service that is offered to service members free of charge, particularly as part of a pre-deployment work-up. Before sending them to a legal officer, I always counseled my Marines to be very careful about who they might give a power of attorney to, and that if there was any doubt with respect to their trustworthiness not to do it. A limited power of attorney usually could also be made available. In the event of your demise or prolonged incapacitation, a power of attorney could save your loved ones a great deal of hassle and grief, and may enable them to do you a lot of good when you are unable to fend for yourself. Key element was trust; if they (the person who would receive your power of attorney) can't be absolutely trusted you were much better off without it.