Dont want to start a debate here. In Islam state has the right to ask people to deposit part of their money under any pretext. This is now called tax. It was always there if you go through the history. Zakat and Taxes are two different things so please do not mix it. None of the reknowned ulema from various countries and backgrounds do NOT find taxes unislamic. How can you find it unislamic..??
Moreover, in Islam state has the power over everything as long as it does not clash with Islamic rules. This is done so that there is only 1 governing authority and not a state within a state like Pakistan current situation.
It is your duty to pay tax. Dont expect the government and politicians to do their part when you are not willing to do your own. If your brother does not offer prayer, this does not absolve you from offering prayer. That is why everyone will be accountable for his own actions.
No more debate..!!!