White Stripes tune

[Roy G <rgermon@xxxxxxxxxxxx>]

Hello all,

There's a tune called "7 Nation Army" by a band called "The White 
Stripes".  The bass line is catchy, and has been rattling around in my 
head (without much company) for weeks.  Tonight I pulled out my pockey 
piano (aka the chromatic harp) to see if I could figure it out from 
memory.  I started on "C" for convenience, and this is what I figure the 
opening line is:

C C Bb C Bb Ab G

Now the fun begins.  I kind of thought it was in the key of the first 
note (I'm using C), but that's a pretty odd collection of notes for key 
of C...expecially the Ab seems out of place.  My next idea was F.  It 
looked like it would play well in 2nd position on a Bb (key of F) even 
though there is no F in it...It's a nicer fit.  The only oddball (in 2nd 
position anyway) is ending on the II...3d''.  Can be done but not very 
well by me just yet.

I have two lines of questioning:

1)  Anyone know the song?  Do you know what key it is actually in, and 
which note of the bass riff that coresponds to?  Do I have the riff 
right (relative pitches, not absolute)?

2)  Given the above notes, what diatonic harp will this play well on?  
I've checked playing it in the key of C in first through 3rd (C, F, and 
Bb harps), as well as F in second position on a Bb harp, and none of 
them lay out super nice.  I might be missing something obvious.

Thanks,
rg