Russian President Vladimir Putin calls the White House to inform them that the Russian military is standing down a military exercise currently in progress. This is done both as a gesture of solidarity with the United States, and to reduce the risk of something happening due the high tension currently being experienced.
At about this time, the blast doors at NORAD’s operations center in Cheyenne Mountain, Colorado are closed. Cheyenne Mountain is designed to be able resist a nuclear attack when buttoned down.
Finally, remember the Matthew Broderick movie “War Games”? At about this time, Defense Secretary Donald Rumseld orders the U.S. Armed Forces to go to DEFCON 3. This is one step below preparation for war.