calling a cap-and-trade system a "tax" is nothing but a semantic game. a cap-and-trade system is a system where the government issues a finite number of pollution permits and private parties have the right to buy and sell those permits. the cost of such permits would go to the seller, not necessarily the government although initially the government would sell the permits, later private parties could buy and sell them to each other. it's not a tax. it's a market.
back when i was in law school, cap-and-trade was the new innovative republican supported system for environmental regulation. the idea was to abandon the top-down approach of simply banning pollutants and to replace it with something that used market forces to put a value on clean air and water. cap-and-trade was first tried in this country when the first president bush won the passage of the 1990 clean air amendments, which included a cap-and-trade system for sulfur dioxide (the substance blamed for acid rain). that system has proved to be "immensely successful in achieving its goals" so the obama administration is seeking to extend that success to other pollutants.
unfortunately, the republican party has changed a lot in the past twenty years. it has gone from a party that believed in using market forces to solve problems to one that has knee-jerk opposition to any environmental proposal and calls anything it doesn't like a "tax." so now we're in this weird situation where a democratic president is proposing an originally republican solution, with the modern senate republicans opposing the plan. they don't really have an alternative. they just don't like it, so they call it a "tax", even though it clearly isn't. if carbon trading is a "tax" because it costs the permit purchasers money, then every purchase in the economy would also be a "tax." if you follow their argument to its logical conclusion, capitalism vanishes entirely.
why do senate republicans hate capitalism?