If the crew is properly trained it can be underway in less than an hour. Personnel ashore can be ferried out by chopper to join the ship.
Of course, if the missiles are already flying when the word comes down all bets are off.
Our tour guide absolutely showed me the readiness of our sailors and the hardware that they could launch on any short notice if needed.
I love our men and women that keep us strong. I’m still on my high for how much those sailors love us civilians when we visit their boats. I want to sign up, but at 46 years I suppose I can only give my moral support.