Presidents are often viewed as national policy leaders. Yet, they increasingly use negative rhetoric to attack the opposition rather than forge legislative compromise, contrary to theories of going public. Why? I argue presidents facing congressional obstruction eschew short-term policy persuasion. They speak as negative partisans to mobilize co-partisans and shape the longer-term balance of power in Congress, improving future policy-making prospects. I collect all presidential speeches delivered between 1933 and 2024 and use transformer methods to measure how often, and how negatively, presidents reference the out-party. They do so when the policy-making environment is unfavorable: when majorities are tenuous, government is divided, and as elections approach. I provide additional support with a case study of Democrats’ 2009 filibuster-proof Senate majority. Finally, this rhetoric has behavioral impact: presidential negative partisanship decreases co-partisan approval of the opposition. This research alters our understanding of going public and reinforces the partisan dimension of modern presidential representation.