That's only half the battle since you still need to get past the TSA checkpoint so if the flight is important to you, you'll get to the airport an hour early ju

That's only half the battle since you still need to get past the TSA checkpoint so if the flight is important to you, you'll get to the airport an hour early just in case the line is significantly longer than usual. Over the past 6 months, I've spent nearly 60 minutes in security more than once due to equipment failure and/or understaffing. Trains are a good backup to airports since airplanes can be grounded (or highly delayed) due to weather, security concerns, equipment problems at the airport, etc. Trains are not (generally) subject to the same concerns so make a good backup. I was in Japan recently and my intercity flight to a city 300 miles away was canceled due to an incoming Typhoon. I was able to book a high speed train that got me in there to catch my flight (and depart before the typhoon hit that airport too). When a blizzard hits NYC, all you can do is sit it out and wait for flights to resume and it can sometimes take days to find an available seat.