Metro, for reasons that defy comprehension, has decided that the next line to be opened is the Yellow, at the end of April. That's a bum choice. The right one is the Blue Line southward to the Huntington station below Alexandria.

Both lines have been built and ready to go for some time. The constraint has been the shortage of subway cars, deliveries of which are far behind schedule. If Metro now thinks that it has enough cars to extend service, it is the Huntington section that needs to come first.

The Yellow Line would only connect points that already have subway service. Running between National Airport and Gallery Place, it merely provides a shortcut. It won't be truly useful until it is completed into the heavily populated neighborhoods north of Gallery Place. Opening the Blue Line, in contrast, would provide an important expansion of service to new areas. It would open the first stations in Alexandria and in Fairfax County. It would cross the Beltway for the first time in Virginia, and reach the first Virginia station to provide commuter parking.

Metro's station at National Airport makes a dreadful terminal. The station itself is poorly designed for the mixture of hurried commuters and confused visitors. With the heavy traffic and frequent jams on the airport roads, it's nobody's first choice for a main transfer point to the bus lines. The sooner the terminal is shifted to Huntington the better.

Metro, it is only fair to say, comes under great pressure to extend its lines because it is delivering on its promise of reliable and convenient service. It is now an essential part of the daily life of the whole metropolitan area. Its crews are doing a fine job of keeping both trains and stations safe, clean and comfortable. If people didn't like Metro, perhaps it wouldn't make much difference which lines opened when. But they do, and it does.