This faded photo shows the Charlestown Navy Yard on March 19, 1920. In the foreground is the destroyer U.S.S. Preble, which was commissioned that day. Behind her is the U.S.S. Constitution. In the background, you can see the cage masts and three funnel arrangements of pre-dreadnought battleships of the Virginia or Connecticut class.
In those days, the Yard was a busy and interesting place, and Boston had militarily significance. For example, pre-WW1, Germany had colonial aspirations in the Caribbean and South America. A significant piece of the Kaiser's war plan involved detaching part of the German fleet to shell Boston and New York, while the army occupied Puerto Rico, Cuba and the Panama Canal Zone. He counted on "shock and awe" to knock a panicked America out of the war. Boston would have played the role that Pearl Harbor played three or four decades later.
Anyway, the photo gives an idea of what we would have fought with.