The US Military is a logistics organization that happens to fight wars.
During the American Revolutionary War where the Americans moved the artillery from Fort Ticonderoga to Boston over the winter of 1775-6 (still an era where the military response to winter was to hunker down somewhere and wait for spring before doing anything), and then proceeded to install them on heights overlooking the harbor overnight.
In WWII, the US managed the astounding feat of supplying the majority of the logistics on what was effectively three separate fronts (North Africa and later the Western Front via the semi-interdicted Atlantic, the Eastern Front via the Northwest Staging Route and Siberia, and the Pacific Theater, including mainland China via the Hump). It was the experience of The Hump that led the military to try relieving Berlin by air, which almost everyone thought impossible at the time but instead turned out to be a smashing success.
The King's troops, growing up in a climate where snow doesn't (well, in 2018. I don't know about 1756) really stick to the ground, probably indeed would not have expected this.
The problem was more that the professionals couldn't predict the actions of highly motivated amateurs.
Primary Schools in particular are very risk averse now.
The Soviets: "One of the serious problems in planning against American doctrine is that the Americans do not read their manuals nor do they feel any obligation to follow their doctrine."
The Nazis: "The reason that the American army does so well in wartime, is that war is chaos and the American army practices chaos on a daily basis."
America: "If we don't know what we are doing, the enemy certainly can't anticipate our future actions!"
>"I am tempted to make a slightly exaggerated statement: that logistics is all of war-making, except shooting the guns, releasing the bombs, and firing the torpedoes." - ADM Lynde D. McCormick, USN
For one of their weekend sorties, they had an entire platoon parachute out, and one of the other transport aircraft dropped equipment for creating a runway. At the end of the weekend, they flew back to land and pick everyone and the equipment used to build said runway, and then flew back to the base.
Truly a work of logistical and infrastructure art.
The old Martson matting worked, but were FOD hazards as well since sand and rocks would often come up through the joins. You definitely don't forget landing on one though, really wakes you up as the aircraft shakes itself like crazy on roll-out.
Pretty much all US combat aircraft are tarmac bound due to low mounted engine inlets, with the exception of a couple transports and the A-10.
We didn't have to build a runway or anything like that, they just landed the C-130s on the dirt runway we "tookdown".
--edit--
Now that I think about it that's when we were doing a lot of training on taking down small runways for the War on Drugs -- between the Panama Invasion and Gulf War I. The mission was to jump in, cause a world of hurt to the cartel and then get picked up and fly home.
That's what makes the US military so expensive. On the other hand, the US does so much of this that everybody knows the US can do it. The USMC tries for a high tooth-to-tail ratio, which is great for short wars, and not so good for really long ones. (Wars seem to be either week long or decade long now. Not much in between.)
China is working on getting more capability in force projection, but it's slow going. The USSR had a reasonable capability, which ran down after the breakup of the USSR. Russia is trying to build it back up.