(1) Most countries do not actually have a military. Instead, most countries outsource their security to the US (most common), to Russia (like Belarus)...
Balaji Srinivasan argues the US is withdrawing from its role as global security guarantor, forcing countries to build their own militaries or align with new hegemons like China, Russia, or Iran. He predicts nuclear proliferation and suggests the digital world may preserve order through encryption and crypto.