> If moving stuff through the air would be cheaper than moving it by sea (fuel costs are a major part of shipping costs), then everything would be shipped by ai

> If moving stuff through the air would be cheaper than moving it by sea (fuel costs are a major part of shipping costs), then everything would be shipped by air. This is not the case; sea is the default, and air is premium. Price and pollution are wildly different beasts. Even the types of fuel are different. > Intuitively it makes sense that moving things through air requires more fuel than moving it by sea, since the airplane has to use fuel to offset its lack of buoyancy, while a ship only has to expend energy to actually move. However ships have to push their way through water rather than air. It's a lot harder to walk to the end of the swimming pool through the water than it is to walk 25 metres regularly. I don't think there's an intuitive answer to this.