America's war against the Barbary pirates

there are as many versions of this as there are pronunciations of Steve Decaturs name.

Wooooooo, knowledgeable about history too!

You dupes really believe any sort of arrant crap that is fed to you. This is your propagandist ejukeshon program.

"You can brush your teeth with Agent Orange".

"Come on take this shot of syphilis for your ole Uncle Sam; he'd never hurt you".

Most likely used to keep ones head up. I can't imagine fighting hand-to-hand with one of those things around my neck.
https://www.mca-marines.org/leatherneck/leatherneck-legacy