Recently I stumbled across this academic article about emotional demonstratives or affective demonstratives, which are demonstratives used to "foster a sense of shared perspective and common ground." For example, if I met another Clevelander and said "how about that LeBron James," what I'm really saying is "I assume you, like me, like LeBron James, so we have something in common."
And you know what's magical about the word that? If I had met another Clevelander one year ago and said "how about that LeBron James," I'd have been saying "I assume you, like me, hate Lebron James, so we have something in common."
So the word that gives the sentence a completely different meaning depending on tone and context. It got me thinking about other times a demonstrative like this or that has spoken volumes.
This was part of one of the most iconic quotations about the Cold War: "Mr. Gorbachev, tear down this wall!" I think the sentence kind of hinges on the word this. Reagan was standing in front of the Berlin Wall when he said those words, but he needn't have been - everyone on earth who heard the words knew exactly what this wall was. This was the wall dividing freedom from oppression, this was the wall dividing us from them - and this became the symbol of the Cold War.
Another memorable presidential quotation - "I did not have sex with that woman." In this instance, Clinton used that to make it sound like he barely knew Monica Lewinsky, and that he found her contemptible.
And check out all the demonstratives in this section of The Gettysburg Address: "We have come to dedicate a portion of that field, as a final resting place for those who here gave their lives that that nation might live. It is altogether fitting and proper that we should do this." Those men didn't die for this nation - one divided and at war, but that nation - the one our forefathers dreamed of.