Wait, wasn't this guy's name was Joe? Who's this Johnny dude?
Fear not, Shmoopers, for you have not misread an entire novel. The title Johnny Got His Gun comes from a popular ballad from 1917 called "Over There." The song was recorded by 1917-style American idols like Billy Murray (sorry, not the one from Ghostbusters, though that would have been awesome) and Nora Bayes.
The song was basically like: "Hey, Europeans, here comes America to kick some butt." It's pure, grade-A cheese. Have a sample:
Johnny, get your gun, get your gun, get your gun.
Take it on the run, on the run, on the run.
Hear them calling you and me,
Every son of liberty.
Hurry right away, no delay, go today.
Make your Daddy glad to have had such a lad.
Tell your sweetheart not to pine,
To be proud her boy's in line.
Over there, over there,
Send the word, send the word over there
That the Yanks are coming, the Yanks are coming…
There's an optimistic call to arms if we've ever seen one. (We've got to admit it's kind of catchy, too.) Here's the message: make your country proud, make your family proud, make the girl you like proud, save the whole freakin' world because you're awesome.
By changing the first line to the past tense, Trumbo is suggesting that we think about the aftermath to a song like this. There are a few ways of reading the title grammatically: What exactly is the gun that Johnny/Joe got? Or is it that Johnny/Joe went and got his gun when he was called, and the events in the book are the result? Also, why is the main character named Joe and not Johnny?
So don't be tempted to accidently call the book "Johnny Get Your Gun." It's in the past tense on purpose. This is book is totally about consequences; everything that happens in this book in real time happens after Joe left the war.