Millions of Americans file their federal income tax returns this week. These pieces from our archive examine the incredible stakes of tax policy—from Emmanuel Saez and Gabriel Zucman’s powerful case for a wealth tax to Felicia Wong’s chronicle of anti-tax politics, Elizabeth Anderson’s defense of Thomas Paine’s vision of social insurance, T. M. Scanlon’s critique of the libertarian argument for low taxes and limited government, Timothy Weaver’s postmortem on Trump’s “opportunity zones,” and more.