Congress and the White House are engaged in the most far-reaching debate about Medicare in the health program's 46-year history, an epic struggle that could bring significant changes in how the government helps seniors and others pay for their care. Medicare faces a daunting financial crisis, forcing lawmakers to confront stark choices. Should younger people pay more to support the program? Should they assume that Medicare won't be around in its current form when they're ready for its coverage? Should seniors pay higher deductibles? What's the government's responsibility to the very ill and elderly who live on fixed incomes and need acute care? In many ways, this is a debate about one generation's obligations to another — and about the role of government in caring for society's most vulnerable people. It's a struggle whose outcome may not be resolved for years, until a consensus is forged.