Stanley Kubrick, Terry Southern, Peter George - Dr. Strangelove - "Your Commie" lyrics

Your Commie has no regard for human life, not even his own. And for this reason, men, I want to impress upon you the need for extreme watchfulness. The enemy may come individually, or he may come in strength. He may even come in the uniform of our own troops. But however he comes, we must stop him. We must not allow him to gain entrance to this base. Now, I am going to give you three simple rules: First, Trust no one, whatever his uniform or rank unless he is known to you personally. Second, anyone or anything that approaches within 200 yards of the perimeter is to be fired upon. Third, if in doubt, shoot first and ask questions afterwards. I would sooner accept a few casualties through accident than lose the entire base and its personnel through carelessness. Any variation on these rules must come from me personally. Now men, in conclusion, I would like to say, that in the two years that it has been my privilege to be your commanding officer, I have always expected the best from you, and you have never given me anything less than that. Today, the nation is counting on us. We are not going to let them down. Good luck to you all.