This is from Anais Mitchell's incredible folk opera "Hadestown". It's my personal favourite so i
 thought I'd have a go at getting the chords down. I know this isn't how she plays it
 as i've seen a few live videos and she has the capo at the
 4th fret so must be in a weird tuning! 
These are the implied chords though:

Em - 022000
Dsus2 - 000230
D - 000232
Dsus4 - 000233
G - 320033
G/f# - 200233

Capo 3

Em  Dsus2-D Em G-G/f#-Em

Em (022000@1)                  Dsus2-D                  Em (022000@1)                  G-G/f#-Em
Why do we build the wall, my children my children why do we build the wall
Em (022000@1)                  Dsus2-D-Dsus4-D               Em (022000@1)                         G-G/f#-Em
Why do we build the wall we build the wall to keep us free that's why we build the wall we
 build the wall to keep us free

Em (022000@1)                          Dsus2-D-Dsus4-D       Em (022000@1)                            G-G/f#-Em
How does the wall keep us free my children my children how does the wall keep us free
Em (022000@1)                       Dsus2-D-Dsus4-D                Em (022000@1)                      DHow (xx0232@1)does the wall keep us free the wall keeps out the enemy and we build the wall to keep us free
Em (022000@1)                            G-G/f#-Em
that's why we build the wall we build the wall to keep us free

etc.

the song carries on with the same chord progression thoughout. each choral part 
gets one line longer each time.

enjoy!