The following is a list of Presidents who served in War, rank and honors. I don't claim this to be complete, its just the best I could glean.
Lt. General George Washington, French & Indian, Revolutionary Wars, “Father of Our Country”
General Andrew Jackson, War of 1812, “Hero of New Orleans”
Brig. Gen. William Henry Harrison, War of 1812, “Hero of Tippecanoe”
General Zachary Taylor, Mexican War, “Halls of Montezuma”
Major General Ulysses S. Grant, Mexican War, Civil War, General in Chief
Major General Rutherford B. Hays, Civil War, wounded in action
Major General James A. Garfield, Civil War, Victor at Middle Creek, KY
Chester A. Arthur, Civil War, Quartermaster General of NY
Lt. Colonel Theodore Roosevelt, Spanish American War, Medal of Honor (Posthumously)
Captain Harry S. Truman, World War I, Captain of Artillery
Lt. John F. Kennedy, World War II, Navy Medal, Marine Corps Medal, Purple Heart
Lt. General Dwight D. Eisenhower, WW I & II, Allied Commander in Europe
Lt. Commander Lyndon B. Johnson, WW II, Silver Star
Lt. Commander Richard M. Nixon, WW II
Lt. Commander Gerald R. Ford, WW II
Pilot George H. W. Bush, WW II, Distinguished Flying Cross
George Washington with the highest rank, followed by Ike & Grant.
So we have Teddy Roosevelt with the highest decoration.
It seems JFK may have had the most decorations.
Ike seems to have had the longest service 40 years (1911 to 1951) from West Point to retirement.
Grant is second with 27 years (1839 to 1866) + 2 years as Secrerary of War.
To Join the Company of Military Historians click here