Hmmm. A marathon runner doesn't start by doing the whole marathon that moment. They first must train to be able to run that marathon. An artist is no different, very few people start able to paint beautiful murals. No, most start by tagging, from there your ideas and ability grows and if you stick with it your style develops and you can create some lovely stuff. Street art is all about composition. Composition is key, a simple addition to a sign, a wall that can be painted to look like a face, etc.
Composition:
Plus, Banksy has been in the Louvre, he hung up one of his works there and it stayed there for several days.
Banksy is pretty cool, some of his stuff is excellent. But, John Fekner and Xavier Prou (Blek le Rat) are the real deal though, the real old school stencil artists, Banksy owes a lot to them.
And Strike, street art is about using everything as a canvas, it's about making the world around you yours. Whether that is by writing your name or leaving a footprint in some mud. It's just raw creativity.
It's not for nothing that this years TED Prize winner was a street artist, JR:
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