The Triple Alliance was Italy, Germany, and Austria-Hungary.
Its considered AWOL and punished by jail time. Technically, the maximum U.S. penalty for desertion in wartime remains death, although it hasn't happened since 1945. No US serviceman has received more than 18 months imprisonment for desertion or missing movement during the Iraq war. You will either get nonjudicial punishment or court martial.
Answer:
More than 3 million people (including over 58,000 Americans) were killed in the Vietnam War, and more than half of the dead were Vietnamese civilians.