Mr. President, for too long, asteroids have wandered their way into the inner system and come too close for comfort. We must finally establish a defense against them.
The Death Star is too large for us to build.
The Enterprise is too advanced.
Armed satellites would violate every treaty we have.
Thus, we must build the awesome low-tech Battlestar Galactica, to defend our world against asteroids. Also, against the Cylons, which will be created soon, so we need to get a head start on defending ourselves against the robot uprising. This could be the beginning of the American Starfleet, which will see a massive influx of jobs.
I'm sure Lockheed or Boeing would also appreciate a contract to build an entire squadron of Vipers.