Time Traveller

One Marine kneels down with some sort of weapon you have not seen before and triggers it off. A huge monstrous flame engulfs the machine. You desperately punch at the launch code but nothing happens. Soon the machine and yourself are pounded with gunfire. As a rocket impacts the side of the machine, the machine explodes with you in it. But at least you die knowing that several 1000 people with heart disease will live now that you had killed Johnson.

But if you had just let history stand as it should have been, you would never had to take such action