Robert Rogers founded a fantastic force of Rangers designed to operate independantly behind enemy lines to raid and recon for the British during the french/Indian wars. Long before there was a U.S. marine corps (Mc) to make up we-did-it-first stories to brag about itself, Roger's Rangers were landing by small boats and raiding enemy camps, even mounting guns on boats for shock effect. As usual the truth is more amazing than Mcfiction.
Roger's Rangers would also move at high speed on foot cross country to strike with frontiersman accuracy with rifles at the unexpected time and place.
A good example of this light infantry mobility is the recent film, "Last of the Mohicans" and "Northwest Passage" starring Spencer Tracy.
The best book to read about the exploits of U.S. Army Rangers is LTC John Lock's "To Fight with Intrepidity"
