I think the Vietnam memorial is between the Foggy Bottom (GWU) and Smithsonian metro stops.
Off the top of my head, the Smithsonian stop puts you out right in the middle of the national mall, so you'd still have a bit of a walk. Not too far though.
Several blocks away, take a look online for more specifics. Sorry I don't have it
It's a bit of a toss up. Either Foggy Bottom or Farragut West can be used. Either way you will have about a 10 to 15 minute walk. Foggy Bottom is a tad closer if all you want to see is The Wall. There is also an alternative....close to both stations are "rent-a-bike" stations, where you can rent a bicycle, ride, then return,, you pay the fee. It's a kiosk, not manned. I'd check out the web site before committing to use. We saw many people using, and several different companies (color of bike determines rental company.)
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