I've been on the receiving end of those "moral boosters," and I can tell you from experience, they don't work on the majority of people who are forced to listen to it. Modern day leaders have been taught to poe to their subordinates in order to keep them going, when in reality, it's the truth that sets people free. It allows you to personally reconcile why you do what you do, and why you've committed yourself to doing it.

Lies like this one do no good but to demoralize and already exhausted movement.

What helps people in time of war is to come to the realization that you're already dead, but you do what you do to help those around you make it back home relatively safely.