Do we really need another tax? Why do we need a Carbon Tax? Climate change is from the Sun. Plants breath Carbon dioxide

There should be no carbon tax, we have enough taxes already. If we didn't have carbon dioxide plants would die and seeing that plants give off oxygen and we exhale carbon dioxide, we kind of need each other to survive. Plants use it for photosynthesis.
If you learned about photosynthesis in school, you'd understand that a carbon tax isn't valid to pay for.