Boys and girls! You can help your Uncle Sam win the war - save your quarters, buy War Savings Stamps" poster
The pattern
This still is filed under Civilian war-duty equate.
Define
A civilian act (saving, making, staying quiet) is framed as the same duty as the front.
Mechanism
Moral equate. The small act inherits the gravity of the large one. The ask is ordinary. The meaning is not.
Verdict
We need mass compliance on an unglamorous behavior and can honestly tie it to a shared stake.
Why it works
It appeals directly to children's desire to participate and be helpful in adult struggles. The visual makes Uncle Sam an affectionate fatherly figure directly addressing the youth.
Steal this when
You want to expand your base of support by enlisting a demographic that is usually overlooked, empowering them with a small, achievable task.