Glaciers actually do retreat and advance seasonally or on even longer cycles. Some have terminuses that move back and forth literal miles. One of the key indicators of climate change is the fact that globally, glaciers are retreating more than they’re advancing on average.
Flat cables can be conformant and they still have twisted pairs. Cables just have to meet the physical properties set by the standard.
There’s probably a bunch of reasons for the multi wing design, but the big one is going to be improving lift/carrying capacity without increasing the width.
The most efficient wings for low speeds are glider wings: as long and thin as possible. That makes them inconvenient to pack and folding joints are weak points. The second wing adds lift, but also problems: it’s less efficient than a single wing of the combined length would be and the front wing makes the rear wing less efficient. The winglet improves the situation somewhat. Facing downward also improves maneuverability.
It’s pretty unintuitive because we’re not used to dealing with ocean sized bodies of water in day to day life. Part of the explanation is just that the prevailing winds pile all the water in the Pacific up against the coast, causing higher sea levels on the West Coast. The lower salinity of the Pacific also causes lower water density, which translates to higher sea levels.
It’s not impossible to invade the US. It’s been done several times already, for example 1942 and 1812. Mexico, which shares the same oceanic borders, was invaded by France in 1861 and of course the entirety of the Americas was essentially invaded by colonial settlers.
It’s unlikely for other reasons, but nothing about it is impossible.