I am not sure how this responds to the comment you are actually responding to. You say,

> Governments pay to keep food cheap > A carbon tax will either drive up prices or [drive up prices]

So, this is just number rearranging. The public pays either way. Ok. The comment you replied to says

> Currently the public subsidizes the agriculture industry by paying for the consequences of the industry's carbon emissions.

So the public pays in this case too. More number rearranging. Not at all clear why this makes prices increase.

So why do you think this implies prices increase? Do you think the price of carbon determined by the government is too high? Or do you just want to ignore this externality until we pay it all at once?