Captain you are doing it all wrong...
In order to understand Destroying the rebels you need to realize that everything is controlled by a group of Combine made up of Small Armies with help from Stalkers, Striders, and gunships.
The conspiracy first started during 7 Hour War in City 17. They have been responsible for many events throughout history, including The Black Mesa accident.
Today, members of the conspiracy are everywhere. They can be identified by their kicking of cans.
They want to Kill Gordan Freeman and imprison resisters in Xen using Trains.
In order to prepare for this, we all must buy weapons. Since the media is controlled by Breen we should get our information from Dr. Kliner.