Final answer:
The wearing of full-size US and foreign decorations and service medals is authorized on formal occasions such as military balls and official ceremonies. Regulations vary by military branch and outline appropriate occasions and uniforms for medal display.
Step-by-step explanation:
The wearing of full-size US and foreign decorations and service medals is typically authorized on formal occasions or ceremonies. These occasions include military balls, formal social functions, inaugurations, and official ceremonies requiring formal dress. For instance, historical instances like the African American soldiers from New York being awarded medals by the French government for heroism during World War I, or the medal set of Colonel Elizabeth Smellie, display the formal recognition of service and heroism.
Each branch of the United States military and other countries have specific regulations regarding when and how service medals and decorations should be worn. In the U.S., the regulations are generally outlined in the uniform regulations for each branch of the Armed Forces. In general, full-size decorations and medals can be worn on military uniforms on occasions prescribed by service regulations.