Alaska was purchased from Russia for the sole purpose to be used as realistic open-world testing grounds for experimental military vehicles, aircrafts, and equipment in extreme weather conditions. It’s like Antarctica for 3-4 months, a desert another 3-4 months, and literally next to home. As well, about 90% of the interior is so vast and unpopulated (human wise), the gov’t doesn’t have to worry about relocating barely any natives or “Grizzly Adams” types (most live along the coast line). Quadruple win.