The US is the only major country not to guarantee healthcare to all its citizens.

“The claim's accuracy depends on the definition of "major country," but it is broadly true when referring to developed, industrialized nations. Organizations like the OECD and the Commonwealth Fund consistently report that the U.S. is the only high-income, industrialized country without a universal healthcare system that guarantees coverage for all citizens. While the Affordable Care Act expanded coverage, millions of Americans remain uninsured, a situation not found in other comparable nations like Canada, the U.K., Germany, or Japan, all of which have systems to ensure universal or near-universal access to healthcare. Context: ⚠️ Claim says 'all' but evidence says 'many'. The term "guarantee healthcare" refers to a system of universal coverage, ensuring all citizens have access to healthcare, not necessarily that all services are free at the point of use. Most developed countries use various models (single-payer, multi-payer insurance mandates) to achieve this, while the U.S. relies on a patchwork of private and public insurance that does not cover everyone.”