A terrestrial adversary could be prepping the battlefield. They supposedly submerge under water, so maybe they are just carry supplies close to our coasts or th

A terrestrial adversary could be prepping the battlefield. They supposedly submerge under water, so maybe they are just carry supplies close to our coasts or they are building something. They could also just be prepping a contingency plan that they don't plan to enact unless a war starts between the US and them.