Don't be so sanctimonious about trains working in bad weather

There are many arguments about the benefits of trains over air travel that don't add up. Here is the latest example.
Paul Krugman, in a post that followed a good economics post about mis-specified models, sanctimoniously notes that Brad DeLong is stranded at a DC airport while he is speeding along on the Acela between Boston and NYC. Talk about mis-specified models! If he looked at Amtrak service in the DC area rather than Boston he would know that most train service was canceled in the area for Saturday. It simply doesn't matter if you want to get out of DC by train or airplane in the middle of a blizzard. You aren't going anywhere. Yet even with a blizzard in DC the NYC and Boston airports are open for business, so his travel would not have been affected had he flown. Trains are subject to the constraint of the weather, too.