How Immigration and Federal Funding Sustain American AI Leadership

America's leadership in artificial intelligence (AI) depends on two foundational inputs: international scientific talent and federal research funding. Using hand-collected data on researcher origins and startup founders, supplemented with large-scale datasets linking patents, publications, and funding sources, we quantify the contributions of each input. International researchers account for 66% of new computer science Ph.D.s and constitute the majority of award-winning authors at premier AI conferences, averaging 61% of recipients at U.S.-affiliated institutions across five leading venues from 2013 to 2024. Among authors at U.S. institutions in the 50 most-cited AI papers, 59% are international. International cofounders are present in firms representing over 95% of aggregate valuation among leading private AI startups. Federal research investment supports 75–80% of CS Ph.D. training, doubles patent commercial value when combined with industry funding, and accounts for 91% of elite startup valuations through federally trained founders. Startups combining international founders and federally funded doctoral training account for over $1.6 trillion in valuation, far exceeding all other combinations. Immigration restrictions and federal budget cuts directly threaten the competitive advantages they claim to protect. We present evidence-based policy recommendations to preserve both inputs within current institutional frameworks.