Answer: Logos
In this excerpt, Reagan is using <em>logos</em> in order to convey a message to his audience. Reagan tells us that the United States is pursuing arms reductions. However, he wants to think of how important it is to maintain the capacity to deter Soviet aggression at all levels. He supports this statement by explaining the way the United States will carry this out and by outlining what the consequences of these actions might be.
They would be the first birds to fly there.
I wouldn't use the word "discovered" it just seems a bit off. I'd rewrite the sentence with a simpler word yet easy to say and understand: "When we searched the school for damage, a new broken window was found." I hope this helps you. My apologies if this is incorrect.