WASHINGTON – In a major speech Wednesday afternoon, President Barack Obama fiercely criticized the GOP's long-term budget, drawing a sharp contrast with the Republican vision of government and calling for "shared sacrifice" as he offered his own deficit-reduction plan.

Calling his approach "more balanced," the president proposed to achieve $4 trillion in deficit reduction over 12 years with a four-point plan: Keep domestic spending low, cut the defense budget, improve health care efficiency, and end the tax cuts for the wealthiest Americans.

"This debate over budgets and deficits is about more than just numbers on a page, more than just cutting and spending," Obama said at George Washington University. "It’s about the kind of future we want. It’s about the kind of country we believe in."

Amidst a national debate about the future of so-called entitlement programs, Obama offered a stirring defense of Social Security, Medicare and Medicaid. "We are a better country because of these commitments," he said. "I'll go further – we would not be a great country without those commitments."

The president criticized the House GOP's budget that seeks to cut trillions in federal spending while privatizing Medicare over ten years and slashing taxes on the rich, calling it a "deeply pessimistic" vision for America, one that declines to take care of seniors and poor people or invest in infrastructure.

"It’s a vision that says America can’t afford to keep the promise we’ve made to care for our seniors," Obama said of the plan authored by House Budget Committee Chairman Paul Ryan (R-WI). "Put simply, it ends Medicare as we know it."

"I will not allow Medicare to become a voucher program that leaves seniors at the mercy of the insurance industry, with a shrinking benefit to pay for rising costs."

Obama said the deficit was significantly exacerbated by the Bush tax cuts for high income earners, and promised to rescind them. "We made the problem worse with trillions of dollars in unpaid-for tax cuts," he said, "tax cuts that went to every millionaire and billionaire in the country; tax cuts that will force us to borrow an average of $500 billion every year over the next decade. "

"We cannot afford $1 trillion worth of tax cuts for every millionaire and billionaire in our society," he said. "And I refuse to renew them again."

Obama vigorously defended liberalism at various points in the speech, making a case for the role of government as a force for good.

Watch Obama take on the GOP budget, via CNN's Newsroom on April 13, 2011.

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