why does gillard call co2 'carbon pollution'?

We've already had a thread debating pollutants, but why does Gillard keep calling co2 "carbon pollution".

On the surface, it seems a little play on words is the best way to sell her controversial tax to the people, but isn't this playing on the gullible?

This is a genuine question and would be interested to hear what others, especially those who think this tax is a good thing, just why she keeps referring to it as "pollution"? And she is also supporting ads that show co2 as being something very dirty.

If she is listening to the CSIRO, surely they would have helped her with the correct terminology?

Any thoughts?