In the pre nuclear era, people could console themselves with the knowledge that though they might not live to see their objectives realized, their children or grandchildren might. The invention of nuclear ons changed the situation entirely. There existed a real possibility that the whole human experiment would be cancelled midway. Now we have world leaders who were ratcheting up the tension toward nuclear war communicating via letters,. It'll take half a day from the time, you know, one side writes the letter, gets it hand delivered to the other side and then read. A lot can happen in a real time crisis in half a day.