Isn't there universal health insurance in America? Why many Americans can't afford high medical expenses.

There is no universal health insurance in the United States. Obama plans to implement universal health insurance in the United States, but now many people oppose it and it is difficult to implement it. The United States is also the only developed country without universal health insurance. Moreover, American medical insurance is not the social security like China. They are private insurance companies, all for profit, and often refuse reimbursement under various excuses.