Best blues guitarist, Clapton or Green

Never got to see Stevie in concert, but for my money he is the blues guitar king. If you ever saw the Austin City Limits featuring SRV you would be picking your jaw up off the ground. He was truly one with his instrument.

I have had the privelege of seeing and hearing Peter Green and Eric Clapton many times. I saw Green with the first Fleetwood Mac tour in the 60s. Clapton several times with each of his incarnations starting with Cream (5X). Green has been my favorite white blues guitarist since the first time I heard him but I cannot disagree with the other contributors that the great black guitarists played from another dimension. No race owns the blues but playing them and feeling them are obviously not the same thing and invariably, in my experience,white musicians have more often played them. Robert Johnson would be my top nomination for sheer creativity and interpretation.

another vote for SRV watch his Austin City limits performances they are awesome.
also try Buddy Guy he plays with emotions

Albert King and Muddy Waters must be mentioned here. Anything live by either artist will let you know what the blues is all about. I prefer the LPs. THey have music on both sides!

Not sure Blues music has (or should have) real stictly defined boundries. To claim that one guitarist is the BEST could put some heavy blinders on the concluder. A few other greats that I haven't seen mention of:
Eddie Guitar Slim, SRV and Zappa were big fans. You might be too if you like the ice pick to the forehead tone later employed by Albert Collins. You can hear him alot in F.Z's playing. Unfortunately, he died from the hard life way too young.
Roy Gaines is good too, Okie Dokie Stomp from his Gainlining Lp is a wild adrenaline hurricane that's fun to go back to.
Jean Paul Bourelly, He's put out a ton of stuff and I haven't heard alot of it, but the Rock the Cathartic Spirit release explores the slow lysergic blues area Hendrix touched on as well as anything I've heard (an amazingly well recorded disc).
David Fiuczynski does highly intoxicating Blues warpage, he's criminally under recognized and waayyy too good to be left out of this kind of thread. Might want to start w/ Lunar Crush or Amandala.