The Inflation Reduction Act signed by President Biden on August 16, 2022, allocated $80 billion in additional funding for the IRS. While Democrats unanimously supported the bill, not a single Republican voted in favor of it. The first legislation advanced by the new Republican majority in 2023 was to repeal this increase in IRS funding. Given the diminished state of IRS enforcement capacity, increasing the resources devoted to tax enforcement seems like an obvious imperative without a clear partisan valence. One might think that political and ideological battles would be fought over what the tax law is, not whether the IRS has the resources to enforce it. But IRS funding has become a major political point of contention. Why is tax law enforcement such a partisan issue? In this Article we propose an answer. We argue that the income tax is the primary instrument for income redistribution, and so the efficacy of tax enforcement shapes people’s support for redistribution. When the IRS makes sure people pay their taxes, support for income redistribution increases. And when the IRS is unable to enforce the nation’s tax laws, support for income redistribution decreases. Thus, for political progressives increasing tax enforcement generates a double dividend. It both provides more funds for redistribution and also increases political support for redistribution, which can then be translated into redistributive changes to the tax law. For symmetric reasons, reducing tax enforcement generates a double dividend for those who disfavor income redistribution. To support our theory, we use unique data from the General Social Survey on perceptions of tax law enforcement. We show that perceptions of tax enforcement are strongly correlated with redistributive preferences. Specifically, people who think that tax law is underenforced are less likely to support income redistribution. We find similar results when looking at specific redistributive welfare programs. To disentangle causation from correlation, we administered a national representative survey which specifically asked about the effects of increased tax law enforcement on support for redistribution. Thus, tax law enforcement does not only determine the amount of tax revenue we collect; it also shapes our redistributive preferences which in turn affects our redistributive polices. This means that as long as our political parties are divided about the desirability of income redistribution, the political battles around IRS funding and enforcement are not likely to wane.