Why is faster than light travel impossible?

Okay in layman terms... Electrons and protons in atoms travel at the speed of light. If you were to build a ship that travels at the speed of light, then the ship will be traveling at the same speed as the atoms that make up the ship. At that point, your ship would begin to lose cohesion. It would begin to break down at the molecular level. You would have no ship. Then you would be screwed.