Of wars of any duration (there by ruling out Grenada, Panama and Desert Storm) we find the following exceptions
The Revolution. "Don't tread on me", "Live free or Die" "Liberty or Death"
The Civil War. "The Union Forever" or random screams AKA the "Rebel Yell".
Viet Nam "N days and a wake up" (where N equals number of days left in country, normally under 335 (one year, less one year's worth of leave == 335 days 'in country'))
The Long War AKA Global War on Terror, AKA Enduring Freedom. "Let's Roll". (see footnote)
This says something about both what the war is about, and what the troops are thinking. Of these, only one, that for The Long War is a take action sort of thing. I'll grant it's also a memorial quote as well.
I'll also grant I don't have a clue about the War of 1812 and the Mexican American war.
Like I said, random thought.
Footnote. For a while I was following Mr. Pournell's lead and was calling the war between the US and the USSR (1917-1989) "The Long War", but the US Military is now calling the GWoT "The Long War" now. I'm not sure how I feel about that, but I strongly suspect my preferred choice "The Final Crusade" would not be taken. Still does my heart good to know that one of the men calling in air strikes on Taliban positions is, in his heart of hearts a Paladin, a follower of the Lion Hearted King and a Crusader for Good.