Create a stong national space defense system of starships to protect against the aliens.

As humans and their technology evolves, we inch closer and closer to space. And with the near certainty that we are not alone in this universe, it's about time we turn to interplanetary defense, with a national space defense fleet, consisting of 50 Flagships, 500 Starcruisers, and over 50,000 combat starships. This is only necessary because of the fact that at any moment we may be invaded by aliens. As a national fleet, called the NSDFA (National Space Defense Fleet of America) could potentially save the lives of all 7 billion people in the world, this is definitely a problem that we must faced sooner or later.