The intent of the Military Code and all acts of the state affecting the military forces is to conform to all acts and regulations of the United States affecting the same subjects, except as otherwise expressly provided by chapter 192A with respect to military justice, and all acts of the state shall be construed to effect this purpose, and anything to the contrary shall be held to be null and void as long as the subject matter shall have been acted on by the United States; and upon any subject not acted upon with reference to these matters by United States authority, any act of the state shall be in full force and effect.