Butcherboy, The words "Target" and "Commitment" are not the same. I expect to see the green movement try to misrepresent them as being the same.
Other countries are not introducing carbon taxes. For us to do so unilaterally will warp the energy economy and have unintended consequences.
Consider for a moment the logic of Australia exporting coal and bauxite halfway around the world, there the coal is burnt to refine our bauxite int Aluminium. Far more efficient for us to turn it into Aluminium, yet a carbon tax will skew it the other way.
The same will apply to all other mineral processing and manufacturing. Even agriculture will be more expensive in Australia than other countries.
Either a carbon tax has to be universal or it will disadvantage only those who apply it.
If you believe in AGW a far more effective solution is to invest in energy efficient technology such as battery cars and low cost carbonless generation.