They do cause economic decline, how can they not? Look, there are X number of available dollars for each of us to spend. When you remove a portion of those from each house hold, said household has a decline in their economy. That Ty is "IT" by definition. Since it is caused by the tax then it is not only honest but very accurate. Any stretch that you are suffering from is the one to seperate the two.
That said, an income tax doers not get totally redicules until you compare the maximum possible income from it with the current deficit spending of the state.