Fear not the Marines still train to use them:

The Virtues of Stubbornness: Mules at War

I suggest the key remains looking at what is being carried by the troops on operations. 70-100lbs load for a day patrol (6 hr ?) ... I can't imagine what 'essential' equipment comprises those loads.

Quote Originally Posted by carl View Post
Why not use an actual horse, mule or donkey? They don't need batteries.
The Comanches taught them to be quiet. Mules were used to carry things for the Army soldiers and Apache scouts when they ran down the other Apaches. They worked great and those ops if I remember correctly were paragons of mountain mobility and persistence.