The Pentagon Actually Does Have Contingency Plans for Alien Invasions From Outer Space
The goal of the US military’s various contingency is to be prepared for if or when the brown stuff hits the fan. If that happens, rather than run around like chickens with their heads cut off, the powers that be want a blueprint ready on the shelf to dust off and carry out. Or at least to use as a starting point for further plans, more narrowly tailored to a real world scenario that resembles the one for which a contingency plan exists.
The plans are sometimes farfetched – sometimes because somebody got carried away. Other times, because the goal is simply to train planners on the nuts and bolts of contingency planning. Some of them are pretty zany. As in far zanier than even alien invasions, as depicted in Mars Attacks! Of the farfetched plans, few are zanier than CONPLAN 8888. Also known as Counter-Zombie Dominance, it is a US Department of Defense Strategic Command plan to defend against a possible zombie apocalypse.