Income tax in the United States These treaties reduce the chance of double taxation by allowing each country to fully tax its citizens and residents and reducing the amount the other country can tax them. Generally the treaties provide for reduced rates of tax on investment income and limits as to which business income can be taxed. The treaties each define which taxpayers can benefit from the treaty. The United States social insurance system is funded by a tax similar to an income tax. Social Security tax of 6.2% is imposed on wages paid to employees. The tax is imposed on both the employer and the
Income tax in the United States on saved income is itself taxed. To the extent that this is considered unjust, it may be remedied in a variety of ways, e.g. excluding investment income from taxable income, making investments deductible and therefore only taxing them when gains are realized, or replacing the income tax by other forms of tax, such as a sales tax. Some economists believe income taxation offers the federal government a technique to diminish the power of the states, because the federal government is then able to distribute funding to states with conditions attached, often giving the states no choice but to submit to