There have been many arguments on the "fairness" of the US tax system, which is mainly progressive on the federal level. Go to https://taxfoundation.org/2021-tax-brackets and look at the current updated 2021 tax brackets and tax rates for federal income tax. Based on the data given, do you think the current system is fair or not? Note on the same site you can use the search engine to look at income tax rates for previous years if you want a comparison. What might be some "equity" or efficiency issues around tax proposals such as expanding the tax rate on the very wealthy or tax cuts for businesses and high-income earners.